Details for Passive Houses: Renovation: A Catalogue of Ecologically Rated Constructions for Renovation 9783035607543, 9783035609530

Table of contents :
Table of content
1. Introduction
2. Basics
3. Building tasks
Buildings erected up to 1918
Buildings erected from 1920 to 1950
Buildings of the 1950s and 1960s
Buildings of the 1970s
Buildings of the 1980s
4. Functional units and ecological optimization
5. Bibliography

Citation preview

Details for Passive Houses: Renovation

IBO – Austrian Institute for Building and Ecology (Ed.)

Details for Passive Houses: Renovation A Catalogue of Ecologically Rated Constructions

Birkhäuser Basel

Editor: IBO – Austrian Institute for Building and Ecology GmbH 1090 Vienna, Alserbachstraße 5 Authors: DI Thomas Zelger, Mag. Hildegund Figl, DI (FH) Astrid Scharnhorst, MSc, DI Dr. Bernhard Lipp, Dr. Tobias Waltjen (all IBO) ao. Univ. Prof. DI Dr. Thomas Bednar, DI Paul Wegerer, DI Johann Schwaller, all TU Vienna (humidity simulations) Ing. Jürgen Obermayer (building services), DI Michael Steinbrecher (drying out of walls), Arch DI Martin Wölfl (architectural aspects), DI Arch. Martin Ploss, Energieinstitut Vorarlberg (costs and cost effectiveness) Coworkers IBO: Ing. Mag. Maria Fellner, Andreas Galosi, MSc, DI (FH) Felix Heisinger, DI Wolfgang Huber ✞, Mag. Veronika Huemer-Kals, DI Lisa Kögler, DI Erna Motz, Mario Schmitradner, MSc, DI Tobias Steiner, Dr. Caroline Thurner (all IBO) Consultants: Arch. DI Heinz Geza Ambrozy (timber construction details), DI Dr. Karl Torghele (connections, sound insulation), DI Walter Pokorny (building physics), Clemens Häusler, MSc (building physics), DI Michael Steinbrecher (structural engineering) Editing: Tobias Waltjen, IBO Translation from German into English: Rupert Hebblethwaite, Vienna; Brian Dorsey Layout and cover design: Gerhard Enzenberger, IBO Production/Project management: Angelika Heller, Birkhäuser Verlag GmbH, Vienna Printing: Holzhausen Druck GmbH, Wolkersdorf Printed with financial support from

Federal Ministry for Transport, Innovation and Technology

Library of Congress Cataloging-in-Publication data A CIP catalog record for this book has been applied for at the Library of Congress. Bibliographic information published by the German National Library The German National Library lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.dnb.de. This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in other ways, and storage in databases. For any kind of use, permission of the copyright owner must be obtained. This publication is also available as an e-book (ISBN PDF 978-3-0356-0754-3) and in a German language edition (ISBN 978-3-0356-0954-7). © 2017 Birkhäuser Verlag GmbH, Basel P.O. Box 44, 4009 Basel, Switzerland Part of Walter de Gruyter GmbH, Berlin/Boston Printed on acid-free paper produced from chlorine-free pulp. TCF ∞ Printed in Austria ISBN 978-3-0356-0953-0 9 8 7 6 5 4 3 2 1

www.birkhauser.com

Preface

For many years the Federal Ministry of Transport, Innovation and Technology has supported research into and the development of technologies for sustainable building. The funding programmes “City of Tomorrow” and its predecessor “Building of Tomorrow” were equally successful. Their outcomes, like innovative methods and technologies, are well established in building practice. When it comes to renovation and refurbishment of the urban building stock, it is a challenge to meet the needs of modern energy and environmental engineering as well as the building budget. The programme “City of Tomorrow” addresses these questions to reduce energy demand and to enable the use of renewable energy resources. Passive house components play a crucial role. The Passive House Catalogue of Building Details for Renovation provides an extensive overview of new methods and technologies for renovation and refurbishment of the building stock, including special energy-efficient solutions for buildings from the 1980s back to the so called “Gründerzeit” in the 19th century. In this context, this publication can be interpreted as an exhibition of applied research in the field of building technologies.

Jörg Leichtfried Federal Minister for Transport, Innovation and Technology

Details of Passive Houses: Renovation

V

Table of content

Introduction 1 Modernization for the future: refurbishment with passive house components

2

The building certification of refurbishment projects

3

Basics 9 Applied methods

10

The ecological “payback” of modernization measures

12

The costs and cost effectiveness of refurbishment to passive house level

18

Airtightness 21 The problem of humidity in existing buildings and in their refurbishment

21

The influence of passive house refurbishment on the hygrothermal indoor climate of unheated cellars without dampproofing

26

The influence of passive house refurbishment without dampproofing on hygrothermal behavior in the perimeters of buildings without cellars

41

Internal insulation and the built-in heads of timber beams

48

Microorganisms on the surfaces of façades

66

Comfort ventilation

69

Harmful substances in existing buildings

74

The disposal of typical demolition materials

83

The reconstruction of the original appearance or new design accents

84

Building tasks

85

Buildings erected up to 1918

86

Details base: External wall – basement ceiling slab

90

D01 | External wall with ETICS – insulated external wall in contact with the ground – uninsulated basement ceiling slab

90

D02 | External wall with insulation between the timber construction – external wall in contact with the ground, horizontally sealed and insulated

91

D03 | External wall with insulation between timber construction – cap vault ceiling, insulated on the upper side with fill

92

Details base: Internal wall – basement ceiling slab D04 | Plastered solid brick internal wall – basement ceiling slab insulated on the upper side Details Base: External wall – floor in contact with the ground

93 93 94

D05 | External wall with ETICS – floor in contact with the ground, insulated on the upper side

94

D06 | External wall with ETICS – floor in contact with the ground, insulated on the lower side

95

D07 | External wall with ETICS – horizontal perimeter insulation – uninsulated floor

96

D08 | Limestone external wall with ETICS – floor in contact with the ground, insulated on the lower side

97

Details Base: Internal wall – floor in contact with the ground

98

D09 | Solid brick internal wall – floor in contact with the ground, insulated on the upper side

98

D10 | Solid brick internal wall – floor in contact with the ground, insulated on the lower side

99

Details Intermediate stories: External wall – intermediate floor

100

D11 | External wall with ETICS – intermediate floor, timber beams

100

Details Intermediate stories: External wall – external wall

101

D12 | External wall – plastered solid brick corner, with insulation between the timber construction Details Parapet: External wall – unheated roof

102

D13 | External wall with insulation between timber construction – top story ceiling loose-fill insulation

102

D14 | Plastered solid brick firewall – top story ceiling with loose-fill insulation

103

Details Parapet: External wall – heated roof D15 | External wall with insulation between the timber construction – attic with rafter doubling Details Parapet: External wall – terrace

VI

101

104 104 105

D16 | Terrace door – terrace on concrete floor – timber concrete composite mezzanine floor

105

D17 | Terrace door – terrace with vacuum insulation – timber concrete composite mezzanine floor

106

Details of Passive Houses: Renovation

Table of content

D18 | External wall with ETICS – top story ceiling becomes a terrace, variant 1

107

D19 | External wall with ETICS – top story ceiling becomes a terrace, variant 2

108

D20 | External wall with ETICS – top story ceiling becomes a terrace, variant 3

109

Details interior insulation

110

D21 | External wall with interior insulation – basement ceiling slab, insulated with fill on the upper side

110

D22 | Solid brick external wall with interior insulation – cap vault ceiling, insulation on lower side

111

D23 | External wall with interior insulation – floor in contact with the ground, insulated on the upper side

112

D24 | External wall with interior insulation – floor in contact with the ground, insulated on the lower side

113

D25 | Limestone external wall with interior insulation – floor in contact with the ground, insulated on the lower side

114

D26 | External wall with interior insulation – internal wall with perimeter insulation 0.5 m (horizontal section)

115

D27 | External wall with interior insulation – internal wall with tapered perimeter insulation 0.5 m (horizontal section)

116

D28 | Solid brick external wall with capillary-conductive interior insulation – intermediate floor, timber beams

117

D29 | Solid brick external wall with interior insulation through facing layer – intermediate floor, timber beams

118

D30 | External wall with capillary-conductive interior insulation – top story ceiling with loose fill insulation

119

D31 | External wall with interior insulation, capillary-conductive – loft conversion with rafter doubling

120

Details Roof: Internal wall – top story ceiling

121

D32 | Solid brick load-bearing internal wall/plastered chimney – solid log floor, apartment separation floor

121

D33 | Solid brick load-bearing internal wall, plastered – solid log floor, top story ceiling

122

Details Window: External wall – window

123

D34 | Solid brick external wall with insulation between timber construction – passive house wood-aluminum window

123

D35 | Solid brick external wall with ETICS, tapered – passive house wood-aluminum window

124

D36 | Solid brick external wall with ETICS – double casement window with double thermal insulation glazing, inside

125

D37 | Solid brick external wall with ETICS – double casement window with triple thermal insulation glazing, outside

126

D38 | Solid brick wall with internal insulation – box-type window with internal triple-glazing

127

D39 | Solid brick wall with internal insulation – box-type window with triple-glazing in the reveal

128

D40 | Roof extension with doubling of rafters – roof windows, optimized installation with Purenit-insulated sash and insulated frame, installed flush with roof cladding

129

D41 | Roof extension with doubling of rafters – roof windows, installation with prefabricated insulated sash and wooden batten frame, standard installation

130

Buildings erected from 1920 to 1950

131

Details Base: External wall – basement ceiling slab

133

D42 | Solid brick external wall with interior insulation – basement ceiling slab, insulated on the upper side with fill

133

D43 | Solid brick external wall with façade insulation panel and rainscreen cladding – insulated external wall in contact with the ground – uninsulated basement ceiling slab 134 Details Parapet: External wall – roof, unheated D44 | Solid brick external wall with façade insulation panel and rainscreen cladding – roof with rafter doubling – top floor with fill insulation Details Window: External wall – window D45 | Solid brick external wall with façade insulation panel and rainscreen cladding – passive house window, insulatable

135 135 136 136

Buildings of the 1950s and 1960s

137

Details Base: External wall – basement ceiling slab

139

D46 | Crushed brick masonry with ETICS – concrete hollow block ceiling, insulated on the lower side

139

D47 | Crushed brick masonry with insulation between timber construction – ribbed concrete deck, insulated on the lower side

140

D48 | Crushed brick masonry with ETICS – reinforced concrete basement ceiling slab, insulated on the lower side – basement window, renovated 141 Details base: Internal wall – basement ceiling slab D49 | Crushed brick masonry – reinforced concrete slab insulated on the lower side Details intermediate stories: External wall – intermediate floor

142 142 143

D50 | Crushed brick masonry with ETICS – top story ceiling, insulated on the upper side

143

D51 | Crushed brick masonry with ETICS – top story ceiling, insulated on the upper side (eaves)

144

Details of Passive Houses: Renovation

VII

Table of content Details parapet: External wall – roof

145

D52 | Gable wall made of crushed brick masonry with ETICS – tiled cold roof (verge)

145

Details window: External wall – window

146

D53 | Crushed brick masonry with ETICS – insulatable passive house window frame

146

D54 | Crushed brick masonry with ETICS – insulatable passive house window frame and blind

147

Buildings of the 1970s

148

Details base: External wall – basement ceiling slab

151

D55 | Exterior wall with ETICS – basement ceiling slab, insulated with ETICS on the lower side

151

D56 | Woodchip concrete wall with insulation between the prefabricated timber construction, rear-ventilated – reinforced concrete slab, insulated on the lower side

152

D57 | Woodcip concrete composite block wall with ETICS – basement ceiling slab insulation, with vacuum insulation on the upper side

153 154

Details base: Internal wall – basement ceiling slab D58 | Woodchip concrete internal wall – reinforced concrete slab, insulated on the lower side

154

D59 | Woodchip concrete internal wall – basement ceiling slab, with vacuum insulation on the upper side, cement screed

155 156

Details base: External wall – floor in contact with the ground D60 | Woodchip concrete wall with ETICS – floor with vacuum insulation

156

Details parapet: External wall – roof, unheated

157

D61 | Porous clay block external wall with ETICS – tiled roof with over-rafter insulation and canopy, eaves

157

D62 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, eaves

158

D63 | Porous clay block external wall with insulation between prefabricated timber construction – tiled roof with prefabricated timber components, eaves

159

D64 | Porous clay block external wall with ETICS – tiled roof with over-rafter insulation and canopy, verge

160

D65 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, verge, variant 1

161

D66 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, verge, variant 2

162 163

Details parapet: External wall – heated roof D67 | Woodchip concrete composite block wall with ETICS – reinforced concrete roof as a terrace with wooden grating

163

D68 | Woodchip-concrete composite block wall with ETICS – flat roof insulation under vapor pressure-equalized metal roof sheeting

164

D69 | Woodchip concrete composite block wall, insulated with cellulose between the timber construction, rear-ventilated – flat roof with duo roof insulation

165

D70 | Cavity brick wall with a clinker façade, filled, internal insulation – top story ceiling, insulated under the tiled roof, verge

166

D71 | Cavity brick wall with a clinker façade, filled, internal insulation – top story ceiling, insulated under the tiled roof, eaves

167

Details roof: Internal wall – roof

168

D72 | Concrete block internal wall – flat roof with vapor pressure-equilized insulation

168

Details window: External wall – window

169

D73 | Woodchip concrete composite block external wall with ETICS – passive house wood-aluminum window Details balcony: External wall – balcony

169 170

D74 | Woodchip concrete composite block wall with ETICS – loggia (horizontal section)

170

D75 | Woodchip concrete composite block wall with ETICS – balcony/loggia, insulated on all sides

171

D76 | Woodchip concrete composite block external wall – Wood-aluminum passive house door as balcony door – reinforced concrete balcony/loggia, insulated on all sides

172

Buildings of the 1980s

173

Base details: External wall – basement ceiling slab

175

D77 | External brick wall with ETICS, inside – basement ceiling slab with ETICS, lower side

175

D78 | Reinforced concrete external wall with prefabricated thermal insulation box – basement wall, insulated on the exterior – basement ceiling slab with suspended ceiling and mineral wool insulation

176

D79 | Brick external wall with insulation between timber construction – externally insulated basement wall – basement ceiling slab with suspended ceiling and mineral wool insulation

177

Details parapet: External wall – roof

VIII

178

D80 | Porous clay block external wall with insulation between prefabricated timber construction – tiled roof

178

D81 | External wall with prefabricated insulation box – reinforced concrete duo roof

179

Details of Passive Houses: Renovation

Table of content D82 | Brick wall with ETICS on the inside – reinforced concrete duo roof Details base: Lightweight external wall – basement ceiling slab D83 | External wall with lightweight prefabricated component insulation element – basement ceiling slab with ETICS on the lower side Details external wall corner: External prefabricated lightweight wall – External lightweight wall

180 181 181 182

D84 | External wall with lightweight prefabricated component insulation element – plastered prefabricated lightweight wall variant 1

182

D85 | External wall with lightweight prefabricated component insulation element – plastered prefabricated lightweight wall, variant 2

183

D86 | External wall with lightweight prefabricated component insulation element – External wall with ETICS with vacuum insulating panels

184

D87 | External wall with lightweight prefabricated component insulation element, plastered, rear-ventilated – renovation with lightweight prefabricated component

185

Details parapet: External lightweight wall – heated roof

186

D88 | External wall with plastered lightweight prefabricated component insulation element – prefabricated roof with tile covering (eave)

186

D89 | Plastered lightweight prefabricated wall – prefabricated roof with tile covering (verge)

187

Details roof: roof – roof

188

D90 | Roof, insulated with prefabricated timber components, roof tile covering, component joint

188

D91 | Roof, insulated with prefabricated timber components, roof tile covering, component joint

189

Details window: External lightweight wall – window D92 | Plastered prefabricated lightweight wall – wood-aluminum window, insulatable Details door: External lightweight wall – door D93 | Plastered prefabricated lightweight wall – passive house wooden door, insulatable

Functional units and ecological optimization

190 190 191 191

193

Insulation: Overview and ecological evaluation

194

External thermal insulation of external walls

205

F01 | Thermal insulation composite system

206

F02 | Timber construction built on site, plastered

208

F03 | Timber construction built on site, rear-ventilated

210

F04 | Prefabricated timber construction, insulation inserted on site, plastered

212

F05 | Prefabricated timber construction, rear-ventilated, insulation inserted on site

214

F06 | Timber construction, prefabricated incl. insulation material, plastered

216

F07 | Timber construction, prefabricated incl. insulation material, rear-ventilated

218

F08 | Anchors at certain points, fastened on site

220

Inner-sided thermal insulation of external walls

226

F09 | Thermal insulation composite system with capillary-conductive insulation

226

F10 | Capillary-conductive thermal insulation between the construction, without a vapor barrier

227

F11 | Thermal insulation composite system with vaporproof insulation material

227

F12 | Thermal insulation composite system with vapor-retarding insulation material

227

F13 | Thermal insulation between the construction with vapor barrier

228

Thermal insulation of pitched roofs

232

F14 | Doubling of the existing roof, on site, facing shell on the inside

232

F15 | Over-rafter insulation, on site

233

F16 | Partial prefabrication, insulation inserted on site

233

F17 | Prefabrication 1

234

F18 | Prefabrication 2

234

Thermal insulation of flat roofs

238

F19 | Rear-ventilated flat roof

238

F20 | Warm roof

239

F21 | Doubling of warm roof onto existing insulation

239

Details of Passive Houses: Renovation

IX

Table of content F22 | Duo roof

240

F23 | Green roof

240

F24 | Terrace, warm roof

241

F25 | Terrace, duo roof

241

F26 | Terrace, vacuum insulation

242

Thermal insulation of the top floor ceiling

246

F27 | Panel on loose fill insulation material

246

F28 | Construction panels on pressure-resistant insulation

246

F29 | Insulation material between timber construction

247

F30 | Insulation between floor spacers

247

Thermal insulation of the basement ceiling on the upper side

250

F31 | Timber floor on loose fill insulation material

250

F32 | Screed on pressure-resistant insulation material

250

F33 | Insulation material between timber construction

251

F34 | Insulation between floor spacers

251

Thermal insulation of the basement ceiling on the lower side

254

F35 | Thermal insulation composite system

254

F36 | Insulation material between construction

254

Thermal insulation of the floor in contact with the ground

258

F37 | Timber floor on loose fill insulation material

258

F38 | Screed on loose fill insulation material

258

F39 | Screed on pressure-resistant insulation material

259

F40 | Insulation material between timber construction

259

F41 | Insulation between floor spacers

260

F42 | Insulation under floor slab with pressure-resistant insulation material

260

F43 | Timber floor on pressure-resistant insulation material, lower-sided

261

F44 | Screed on loose fill insulation material, lower-sided

261

Thermal insulation of the outer side of the external wall in contact with the ground

265

F45 | Insulation material, pressure-resistant

265

F46 | Loose fill insulation, below the soil

265

Balconies and loggias

268

F47 | Insulation of the balcony slab, seal on the insulation material

269

F48 | Insulation of the balcony slab, seal under the insulation material

270

F49 | Balcony, new, extended

270

F50 | Balcony, new, tripod

270

F51 | Balcony, new, thermally decoupled element

271

F52 | Balcony with steel sheet

271

Windows 275 F53 | Wood window

276

F54 | Passive house window frames which additional insulation can be attached to

276

F55 | Passive house wood-aluminum window

277

F56 | Wood PU window

277

F57 | Plastic window

277

F58 | Wood window with existing frame on the outside

277

F59 | Wood window with existing inner frame

277

Bibliography 283

X

Details of Passive Houses: Renovation

Introduction

1 Introduction

Modernization for the future: refurbishment with passive house components

2

The building certification of refurbishment projects

3

Details of Passive Houses: Renovation

1

Introduction Modernization for the future: refurbishment with passive house components At the 2015 climate conference in Paris almost all of the world’s countries agreed to limit global warming to significantly less than 2 °C compared with the pre-industrial age, in order to limit the drastic environmental impact as much as possible. There is a scientific consensus that, in order to reach this target, each person may only emit 100 more tons of fossil CO2 and that the global economy must be CO2 -neutral by the middle of the century [Schellnhuber 2015]. One of the major sources of CO2 emissions is the conditioning of the world’s buildings. In temperate and cold climate zones a significant share of total energy consumption is used to heat these buildings. Much of this is represented by such fossil sources as crude oil and natural gas whereas wood, heat from cogeneration plants and electricity for either direct heating or the operation of heat pumps also play a role in certain countries. In addition to this, electricity in most countries is non-renewable and largely produced from fossil sources and uranium. The refurbishment of buildings to passive house standard as set out in detail in this book leads to heating cost savings of between 75 and 90 %. The large-scale implementation of this approach across the course of the next 35 years is a key requirement for meeting the binding climate protection targets anchored in international law. Conventional refurbishment fails to achieve even half of this potential. The later high quality refurbishment of such “half-refurbished” objects makes no economic sense due to the fact that the cost-savings produced by thermal refurbishment are dependent upon the initial energetic condition. Suboptimally refurbished objects are thus not suitable for high-quality refurbishment until their next refurbishment cycle and hence reinforce this suboptimal situation over many years and decades. The fact that refurbishment with passive house components creates buildings which, in building physics terms, are reliable and, in economic terms, can be heated at low cost will support the creation of an economy free of imported energy. The most physically tangible benefit of passive houses is the comfort provided by agreeable radiance temperatures. High surface temperatures also permit more flexible furniture layouts due to the fact that wardrobes and sofas can also be located against external walls. If renovation work is already pending, passive house refurbishment requires only marginally higher investment costs. For example: • If the external wall already has to be repainted the façade can be simultaneously insulated to a passive house thickness (20 to 30 cm insulation thickness). • If the roof has to be newly covered it can also be simultaneously insulated to a reasonable thickness (30 to 40 cm insulation thickness). • If the windows need to be replaced, passive house windows can be placed in the insulating layer. If the frames are still in a good condition the old glazing can be replaced by contemporary triple glazing. • If the cellars or walls of residential buildings which are in contact with the earth have to be refurbished due to humidity problems a minimum of 20 cm of thermal insulation can be applied to the vertical waterproofing. Alongside high quality thermal insulation, a passive house also requires needs-based controlled comfort ventilation with high performance heat recovery. This guarantees the necessary rate of air changes and the internal air quality. Ventilation plant only works efficiently if a building envelope is air-tight. Non-airtight building envelopes are not only a comfort problem, but also the main cause of damage to buildings. High quality refurbishment avoids such typical problems of conventional refurbishment as the formation of mold (airtight windows and, hence air humidity levels of well over 40 %, cold bridges) in two ways: 1. The temperatures of internal surfaces are much higher due to the increased thermal protection and conscious reduction of cold bridges 2. Needs-based comfort ventilation generally reduces air humidity in winter to below 40 %. The additional costs of passive house components arise principally from comfort ventilation and highquality windows. On the other hand, the increase of insulation thicknesses to passive house levels only involves minimal additional costs given that it is only the cost of the insulating material which rises and this that only represents a small proportion of the total costs in comparison with the material and labor costs which would have arisen anyway (e.g. for scaffolding, the cleaning of old façades, external plaster, adhesives, fixings, etc.). Considering the lifecycle of a building, passive house refurbishment is costeffective. When refurbishing to passive house standard it is very important that projects have an overall concept and that individual measures are coordinated and have a clear objective. These individual measures can then be implemented in phases. In line with the notion of “deep renovation”, each passive house refurbishment measure is designed to realize the entire energy efficiency potential and to leave no potential unused until the next refurbishment cycle. For example, overall concepts can build upon the following possibilities: • Lateral extensions, extra stories and the enclosing of balconies can make a building more compact and reduce transmission losses

2

Details of Passive Houses: Renovation

Introduction • Constructional cold bridges (corners of exterior walls, interfaces between cellar ceilings and walls etc.) can be reduced by appropriate insulation measures. • Airtightness can be ensured by the external plaster if the internal plaster is incomplete or not continued to slab level. • High levels of airtightness must be achieved at connections, openings (e.g. chimneys) and service duct openings! • Unused chimneys can be used for the integration of ventilation pipes. • The enlargement and expansion of window areas can improve daylight levels and increase solar gain. • Centrally located water heating plant and consequently short distribution distances minimize heat losses. • Electricity-saving building services, equipment and lighting increase the efficiency potential of the high quality refurbished building envelope. The high quality refurbishment of a large proportion of existing buildings to passive house standard would allow us the flexibility not to insulate the relatively small number of façades which are historically-protected or hard to refurbish externally for other reasons or, if necessary, to insulate these modestly on the inside – while still enabling us to these heat these buildings over the long-term. This Passive House Building Element Refurbishment Catalog proposes a series of systematic refurbishment solutions using passive house components and describes and evaluates these across their entire lifecycle in line with technical, building physics and ecological criteria. Such specific issues as non-watertight cellars, ground floors which come into contact with the earth, internal insulation, design issues, investigations of hazardous materials and the ecological quality of refurbishment solutions are specially addressed in separate chapters.

The building certification of refurbishment projects A sustainable and economic modernization project should at least meet passive house standards. However, in addition to this basic requirement, other quality criteria such as the minimizing of polluting emissions from – and the ecological quality of – the building materials can also make an important contribution to the sustainable quality of refurbishment measures. This section contains a compact overview of this issue and of several certification systems. In addition to this, this overview uses examples of typical building certification systems to show how much and how strongly this “measured” building quality can be influenced by passive house-related refurbishment measures.

An overview of building assessment systems in Austria While demand for building certification is growing and this has become a well-established aspect of new building projects, the certification of refurbishment objects is much less common. Some certification systems have developed their own criteria catalogs for refurbishment objects (EnerPHit of the PHI Darmstadt, klimaaktiv, BREEAM, DGNB), whereas the strategy of others is to adapt criteria on a case-by-case basis and differentiate between new building and refurbishment projects in individual criteria (LEED®, TQB etc.). The following evaluation systems for refurbishment and new building are offered in Austria: • Passive House Certification and EnerPHit, (www.passiv.de, responsible body: Passivhaus Institut Darmstadt, since 2004 / EnerPHit since 2011) • klimaaktiv Bauen & Sanieren (www.klimaaktiv.at/bauen-sanieren.html, responsible body: BMLFUW – Federal Ministry of Agriculture, Forestry, Environment and Water Management, since 2004) • TQB – Total Quality Building (www.oegnb.net, responsible body: ÖGNB – Austrian Sustainable Building Council, since 2002, successor to the “Total Quality” system) • IBO ÖKOPASS (www.ibo.at, responsible body: IBO – Österreichisches Institut für Bauen und Ökologie GmbH, since 2001) • DGNB Certification System (www.dgnb.de; responsible body: German Sustainable Building Council, in Austria since 2009) • EU Green Building (www.ibo.at/de/greenbuilding, responsible body: EU Commission, since 2007) • LEED®–Leadership in Energy and Environmental Design TM (www.usgbc.org, responsible body: USGBC® – U.S. Green Building Council® / GBCI® _Green Building Certification Institute, since 1993) • BREEAM – Building Research Establishment Environmental Assessment Method (www.breeam.org; responsible body: BRE – Building Research Establishment; since 1990)

Details of Passive Houses: Renovation

3

Introduction The benefits of the building certification of refurbishment measures What are the benefits of the building certification of refurbishment measures? Is refurbishment not already the most sustainable way of building due to the fact that existing resources are used without being devalued? On the one hand, new building can rarely match refurbishment in terms of ecological quality. On the other hand, passive house standard is harder to achieve in a refurbishment than in a new building. However, most refurbishment projects leave enough scope for optimizing their sustainability aspects. Building certification systems offer guidelines for sustainable building which minimize negative environmental effects and maximize comfort while optimizing executional quality in line with the latest technological standards. If the certification team is involved from the preliminary design phase of the design process the best possible results can be obtained at the lowest possible cost. Building certification systems claim to set the agenda for sustainable building – ecologically, economically and socially. Well-balanced points systems quantify the effects of building measures and provide an incentive not to make savings at the expense of the environment. While “Green Washing” seeks to market projects on the unjustifiable basis of an apparently environmentally friendly and responsible image, recognized certification systems are based on transparent criteria and testing processes. The boundary conditions and minimum requirements for the top awards should be based on the latest level of knowledge. Further benefits of the certification of sustainable and high-quality refurbished objects are: • Competitive advantages in sale and letting • Quality assurance (mold, airtightness etc.) • Control of the quality of execution (blower door test, measurement of ambient air quality, noise protection measurements etc.) • Setting of higher building standards (e.g. regarding criteria for energy, ecology and comfort) in the early design phases • Savings during the building process that are made at the cost of executional and ecological quality (airtightness, warm bridges, efficiency of ventilation plant, choice of materials etc.) no longer remain unnoticed thanks to the certification tool • Guaranteeing of increased residential and workplace quality (comfort, ambient air etc.) • Lower operating costs • Stable and higher real estate value (e.g. as pension provision)

Evaluation of refurbishment measures in the framework of building evaluation systems using the examples of EnerPHit, IBO ÖKOPASS, klimaaktiv, and TQB High quality energy efficiency refurbishments using passive house components are mostly integrated into building evaluation systems in the form of such individual criteria as heating energy, final energy and primary energy demand; CO2 emissions during building operation, elimination of warm bridges, airtightness etc. The evaluation of constructional refurbishment measures under the EnerPHit, IBO ÖKOPASS, klimaaktiv and Total Quality Building (TQB) assessment systems are presented below. EnerPHit Standard and Passive House Certification1 As a result of complications caused by the constructional methods of the existing buildings, refurbishment projects are subject to economic and technical parameters which often make it impossible to achieve passive house (new building) standards at justifiable cost. Passivhaus Institut Darmstadt has created an instrument – its EnerPHit form of certification – which is able to comprehensively evaluate the application of passive house components to individual building elements and document improvements in terms of increasing comfort, saving energy and avoiding constructional damage. If more than 25 % of the area of opaque external wall is internally insulated during a refurbishment project then the EnerPHit+i seal is awarded. In the case of particularly ambitious modernization or refurbishment projects with limited constructional constraints, (new construction) passive house standard can also be achieved.

1 Criteria for the Passive House, EnerPHit and PHI Low Energy Building Standard, version 9c, revised 30.06.2016, ed. by Passivhaus Institut Darmstadt

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Passive House Seal

EnerPHit Seal

EnerPHit +I Seal

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Introduction EnerPHit has two alternative verification methods: The building component method with requirements related to building components (the criteria of which are largely identical to those of certified passive house components) or a method with requirements related to entire buildings (energy demand method). Given that the criteria and requirements to be met change in line with building location and climatic zone, EnerPHit certification is possible worldwide. a) Building component method The building component method defines maximum heat transfer coefficients (U-values) for opaque building elements and differentiates between internally and externally insulated walls as a function of the number of degree days. As it is not always possible to justify the cost of completely avoiding thermal bridges in refurbishment projects, thermal bridges are to be incorporated in the calculation of the U-value – as long as these are part of the standard construction of the building component. In the case of transparent building component, the required U-values and g-values are also dependent upon the position of the building component (there is a basic differentiation between horizontal, inclined and vertical glazing). In hot and very hot climatic zones the external colors are also decisive for meeting the cooling load requirements: it is strongly recommended to use “cool colors” with a high solar reflection index (SRI). Air conditioning units require a minimum heat recovery efficiency of 75 % in warm-temperate and cool-temperate climatic zones and 80 % in cold and arctic zones or extreme mountainous locations, and this value is to be calculated by taking the entire ventilation system into account (e.g. including the heat loss due to warm ventilation ducts in cold areas and cold ducts in warm areas). The thermal insulation requirements for building components in contact with the ground are naturally determined from the specific heating and cooling degree days of the location. Exceptions to the EnerPHit U-value rules set out in Table 1 are permitted due to economic considerations or practical constructional reasons (historic buildings, fire protection requirements, etc.). In such cases, however, the U-value may only be exceeded by the absolutely unavoidable amount (and when using this exception clause, the minimum insulation requirements are in any case to be met for reasons of thermal comfort and avoiding constructional damage – see the current version of the EnerPHit certification criteria, www.passiv.de/Zertifizierung/Gebäude).

Tab. 1: EnerPHit Criteria for the building component method (30.06.2016)

An important role in establishing comfort levels in line with EnerPHit is also played by the avoidance of overheating in summer and increased humidity. The proportion of hours in the year with an ambient air temperature over 25 °C is to be limited to a maximum of 10 % in the case of buildings without active cooling and the proportion of hours in the year with absolute internal air humidity over 12 g/kg to less than 20 % in the case of buildings without active cooling and less than 10 % in the case of buildings with active cooling. b) Energy demand method According to the PHPP the specific heating energy demand should not exceed 25 kWh/m² ERA a for cooltemperate climatic zones (in Central Europe) and 35 kWh/m²a for arctic zones (this case can also be applied to mountainous locations). The values for cooling and dehumidification requirements are subsumed, with the limiting value for the dehumidification contribution being applied on a project-specific basis as a function of climatic data, internal humidity load and the number of air changes and being determined automatically in PHPP (Passivhaus Projektierungs-Paket from version 9.0)2 . In the case of both methods (Building component method and Energy demand method) there is an obligation to meet the minimum pressure test air change requirements (for a pressure difference of 50 Pa) of 1.0 1/h for refurbishments. In order to place projects into the EnerPHit Classic, Plus and Premium certification classes, project-specific minimum requirements for both renewable primary energy (PER) demand and – for the Plus and Premium classes – the generation of renewable energy (as a function of the building footprint) have been defined

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2 Passive House Planning Package (PHPP): The energy balance and planning tool for efficient buildings and refurbishments, Version 9 (2015), ed. Passivhaus Institut Darmstadt

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Introduction in situ since 2015. For a transition period, “EnerPhit Classic” standard can also be verified by compliance with the limiting value for non-renewable primary energy whereas the approval of national primary energy conversion factors including the adaptation of the limiting values of the Passivhaus Institut is implemented from PHPP Version 9.6. Renewable Primary Energy (PER) Classic PER-Demand [kWh/(m²a)] ≤ 60 + (Q H – Q H,PH ) • f OPER,H + (Q C – Q C,PH ) • 1/2

Criteria Plus Premium 45 + (Q H – Q H,PH ) + (Q C – Q C,PH ) • 1/2

30 + (Q H – Q H,PH ) + (Q C – Q C,PH ) • 1/2

Renewable energy generation (with reference to projected building footprint) [kWh/(m²a)] ≥ - 60 120 Tab. 2: EnerPHit requirements for renewable primary energy PER (demand and generation in situ) in line with the certification classes Classic, Plus, Premium

Altern. criteria +/-15 kWh/(m²a) deviation from criteria… …with compensation of the above deviation – by different amount of generation

As 85 % of modernizations in Germany take the form of partial refurbishments, step-by-step EnerPHit certification – which includes the issuing of a preliminary certificate after the carrying out of a first important step and the presentation of a refurbishment timetable and comprehensive refurbishment program – is available from 2016. This first important step should be either a reduction of heating energy demand by a minimum of 20 % or 40 kWh/m²a or a reduction of the renewable or non-renewable primary energy demand by at least 20 % or, in the case of several property owners, at least one residential unit should have been comprehensively thermally refurbished or an extension should have been added. EnerPHit and passive house certification criteria and the underlying calculation methodology are subject to constant revision and adaptation in line with continuous technological developments. In the case of building certification, “as a priority, the current criteria and technical rules are always valid (and always to be found under www.passiv.de), followed by the calculation methods described in the PHPP Handbook and PHPP Program.” The assessment of whether the required documents conform to current certification criteria and the issuing of the certificate are carried out by freely chosen certifiers accredited by the Passivhaus Institut. IBO ÖKOPASS The IBO ÖKOPASS was developed as a building passport – especially for residential complexes. It focuses on the subjects of user comfort, healthy living and sustainability and its evaluation categories are 1. Comfort in summer and winter, 2. Internal air quality, 3. Noise protection, 4. Daylight and insolation, 5. Electromagnetic quality, 6. Ecological quality, 7. Overall energy concept and 8. Use of water. The categories can be rated “excellent”, “very good”, “good” and “satisfactory”. The IBO ÖKOPASS has a two-stage evaluation strategy – the evaluation of the design and of the completed object – and includes measurements and site visits. Building physics-optimized refurbishment to passive house quality can score particularly well in terms of the criteria comfort in summer and winter, internal air quality and overall energy concept. If, in addition to this, the refurbishment involves the use of ecologically sustainable building materials, the evaluation in the category ecological quality will also improve. klimaaktiv Bauen und Sanieren klimaaktiv evaluates projects using a 1,000 point formula. Depending on building quality three award levels can be reached: klimaaktiv gold (900 to 1,000 points), silver (750 to 899 points) and bronze (in which all mandatory criteria are met). There are four evaluation categories: Design and execution, energy efficiency, building materials and construction, comfort and internal air quality. A detailed explanation of the criteria can be seen at: http://www. klimaaktiv.at/bauen-sanieren/gebaeudedeklaration/kriterienkatalog.htm. It should be noted that the total of the maximum achievable number of points in all sub-criteria in a category can be higher than the total of the maximum achievable number of points in the category itself. This means that there are different potential optimization strategies for those seeking to achieve the maximum number of points in a category. As one aim of klimaaktiv is to support Austria’s climate strategy, energy efficiency plays a major role (650 of 1,000 points). This requires an efficient comfort ventilation plant with heat recovery that meets the klimaaktiv comfort criteria, the reduction of the energy demand in general and the choice of an energy supply with renewable energy (relevant for CO2 emissions and primary energy demand). Moreover, if ecologically optimized building materials and construction (C) and low-emission products (D2.2) are used, a further 150 points can be achieved. If the construction is also optimized in terms of thermal comfort in summer and life cycle costs were taken into account, a total of 960 points (gold) can be reached by ecological and building physics-related passive house refurbishment measures alone. Total Quality Building (TQB) Total Quality Building (TQB) is compatible with – but more comprehensive than – the klimaaktiv building standard. A maximum of 1,000 points can be achieved and there are no specific award levels. The TQB criteria are divided into five main categories: Location and facilities, economy and technical quality, energy

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Introduction and supply, health and comfort and resource efficiency. The individual sub-criteria are adapted for refurbishment projects. The detailed explanations of the criteria are accessible at: https://www.oegnb.net/en/ tqb.htm. Unlike in the case of the klimaaktiv criteria catalog the weighting of the five main categories is equal – with 200 evaluation points. This means that the influence on the overall result of energy efficiency measures alone is lower (~15 % of the total number of points). The economic aspects of the optimization of building elements across the entire lifecycle of a building flow into the result with at least 65 points. In addition to this, if the suggestions in this book for optimizing building elements are applied, a further 200 points in “E Resource efficiency” and 112 points in “D Health and comfort” and, hence, a total of 527 points (53 %) can be achieved. All other criteria are to be met by additional measures which do not fall into the category of constructional and ecologically optimized refurbishment measures.

Conclusion Building certification systems can support the targeting of the Building Element Refurbishment Catalog in that they can serve as guidelines for selecting sustainable refurbishment measures. There is extensive room for optimizing the sustainability aspects of not only new buildings but also refurbishment projects. At the construction level, the Building Element Refurbishment Catalog is a powerful tool for the implementation of high quality refurbishment which is available to both designers and builders. The cost of building certification should be in proportion to the benefits achieved and can be effectively reduced by the Building Element Refurbishment Catalog – even in cases when constructional details are not precisely used but adapted according to need or where the catalog is only used for selected building elements.

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Basics

2 Basics Applied methods

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The ecological “payback” of modernization measures

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The costs and cost effectiveness of refurbishment to passive house level

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Airtightness 21 The problem of humidity in existing buildings and in their refurbishment

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The influence of passive house refurbishment on the hygrothermal indoor climate of unheated cellars without dampproofing

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The influence of passive house refurbishment without dampproofing on hygrothermal behavior in the perimeters of buildings without cellars

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Internal insulation and the built-in heads of timber beams

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Microorganisms on the surfaces of façades

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Comfort ventilation

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Harmful substances in existing buildings

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The disposal of typical demolition materials

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The reconstruction of the original appearance or new design accents

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Basics Applied methods Lifecycle assessment indicators The following lifecycle assessment indicators were used for the ecological evaluation of the standard crosssections and functional units: • Total non-renewable primary energy (PENRT) • Global warming potential (GWP) • Acidification potential (AP) • Aggregated indicator OI3 The data used for calculating the lifecycle assessment indicators in this book are taken from the IBO Catalogue of Reference Values for Building Materials. The current catalogue was compiled at the end of 2007 for the “Passive House Building Element Catalog” study [IBO 2008] and updated in April 2016. The basic data (normative term “generic data”) for such general processes as energy systems, transport systems, basic materials, disposal processes and packaging materials are largely taken from ecoinvent v 2.1. Some basic data for raw materials and upstream products were collected by the IBO during product evaluation work and research projects. The specific basic parameters and methodic specifications for the building ecology reference values are to be found in [IBO 2010]. For the specific values used refer to www.ibo.at/PH_SAN. Evaluation is made of the manufacturing phase (cradle to gate, modules A1 to A3 in line with EN 15804) and the replacement of building materials upon the expiry of their expected useful life (module B4 in line with EN 15804) during a period of observation of 100 years. In simple terms, the calculation is made as follows: After the end of the expected useful life of a building material the material is produced once again with the number of new production cycles in the entire period of observation being the result of dividing the period of observation by the expected useful life. The cost of removing and building in the renewed materials is ignored. The data in [ZELGER 2009] is used for the expected useful life. In this work, resilient values for the maximum expected useful life were derived from statistical evaluations, in-depth analyses and primary plausibility considerations.

Total non-renewable primary energy (PENRT) Total non-renewable primary energy (abbreviation PENRT) describes the total non-renewable energy resources required to produce a product or a service. PENRT is given in MJ and calculated from the lower calorific value of the energy resources deployed. The Total non-renewable primary energy of all non-renewable resources (crude oil, coal etc.) is given in PENRT. It includes both energetically and materially used resources.

Global warming potential (GWP) The global warming potential GWP describes the contribution of a trace gas to global warming for a time horizon of 100 years compared with carbon dioxide. GWP contains both the contribution of the greenhouse gas emissions to global warming and the quantities of carbon dioxide trapped in biomass. The greenhouse gas potential is given in kg CO2 equivalents.

Acidification potential (AP) Acidification is principally caused by the interaction of nitrogen oxide (NO x) and sulfur dioxide (SO2) gases with other constituent parts of the air. One of the clearly associated consequences is the acidification of lakes and rivers and subsequent decimation of fish stocks in terms of both quantity and diversity. The average “European acidification potential” is used for the calculation of acidification potential. Acidification potential is presented in kg SO2 equivalents.

OI3 Indicator The OI3 indicator is a dimensionless ecological indicator for a building or a thermal building envelope TGH, which is formed from the three indicators: Total non-renewable primary energy, global warming potential and acidification potential. Various OI3 indicator sets are defined depending upon the assessment boundaries and the reference value. In this project the ecological indicator OI3 KON (incl. module B4) is used. Details on the calculation of the OI3 indicator can be accessed at http://www.ibo.at/documents/OI3_Berechnungsleitfaden_V3.pdf.

Waste management indicator (recycling, incineration, dumping) The waste management indicator was used in line with the method in [Schneider 2010], which is briefly set out below; detailed information can be found in the above-mentioned work. Determination and grading of the waste management procedure It is assumed that demolition will be oriented towards recycling. Building elements which can be cleanly separated into homogenous layers are separated into these layers whereas, in the case of layers which

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Basics cannot be cleanly separated, assumptions are made about the interfaces between neighboring materials. If building elements cannot be separated into individual materials these are disposed of together. The waste management procedures and processes are classified on the basis of current waste management practice with the help of an evaluation matrix. The starting point for the evaluation of the characteristics of construction materials is the evaluation matrix developed in ABC-Disposal [Mötzl 2009]. However, a five-step rather than a four-step system is used: Recycling Incineration Reuse or recycling into a technically equivalent Higher calorific value (>2000 MJ/m 3); natural metal and 1 secondary product or raw material halogen content in ppm-range, homogenous material Recycling material can be separated into homogenous As 1, but not homogenous, maximum proportion of 2 materials at low cost and be recycled to a high quality non-organic contaminants 3 M.-% Recycling material is contaminated, can be broken As 1 or 2, but medium calorific value (500–2000 MJ/m 3) up at higher cost and then recycled after processing or low metal or halogen content (= 1 m, thickness approx. 10 cm).

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Basics The influence of refurbishment variants on moisture behavior are analyzed below – as in the case of the existing construction, this takes the form of, firstly, a two-dimensional snapshot taken on the 1st January and, secondly, a comparative simulation of the critical internal corner between the internal plaster face of the external wall and the floor construction during the course of a year. Façade and perimeter insulation/umbrella insulation In this refurbishment variant, 30 cm of insulation is applied to the entire façade including the perimeter. The snapshot taken on the 1st January can be seen in Fig. 49.

low soil moisture

high soil moisture

Moisture content in kg/m 3

Relative air humidity (dimensionless)

Fig. 49: Water content, relative air humidity and temperature in winter following refurbishment with external and perimeter insulation in the cases of both low and high soil moisture

Temperature in °C

As the image shows, the variant with higher soil moisture has a similarly high moisture horizon in the masonry as the existing construction. In this case the external insulation also has a negative effect on the moisture content of the masonry. There is a constant supply of moisture from the foundation due to the fact that the insulation prevents the evaporation to the outside of the water rising up the external wall through capillary action. However, the analysis of the relative air humidity pattern during the course of a year (Figs. 52 and 53) shows an improvement in comparison with the existing construction. This is primarily because the insulation raises the temperature of the entire wall construction which, in turn, reduces the relative air humidity in the critical corner area. External insulation with floor insulation In addition to the external and perimeter insulation the floor which sits directly on the earth is also insulated. In order to achieve this, the entire existing floor construction including the fill is removed and then a classic new floor is constructed, including insulation to either the upper (30 cm EPS) or lower side (30 cm XPS). Fig 50 shows the two-dimensional snapshot taken on the 1st January: this represents a slight improvement on the existing construction in cases of low soil moisture but the relationships are unsatisfactory when soil moisture is high. The results for the insulation to the underside of the floorplate are very similar to those presented here for the insulation to the upper side of the floorplate.

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Basics

low soil moisture

high soil moisture

Moisture content in kg/m 3

Relative air humidity (dimensionless)

Fig. 50: Water content, relative air humidity and temperature in winter with external insulation and insulation to the upper side of the floorplate in the cases of both low and high soil moisture

Temperature in °C

Internal insulation of the external wall and to the upper side of the floor To begin with: the application of internal insulation must always be planned individually for each individual object (see also page 48). Hence, the model presented here applies exclusively to the boundary conditions described here and cannot simply be applied to other objects. This applies in particular to vertical walls without dampproofing which rise out of the earth. There follows the presentation of a model with internal insulation and insulation against the earth which could be used to minimize the loss of heat via the external envelope. A 30 cm thick insulating layer and then a conventional floor construction are built on top of the reinforced concrete floorplate. The internal insula-

Model

Relative air humidity (dimensionless)

Details of Passive Houses: Renovation

Moisture content in kg/m 3

Temperature in °C

Fig. 51: Water content, relative air humidity and temperature in winter with internal insulation, floor insulation and low soil moisture

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Basics tion connects directly with the floor insulation. This avoids thermal bridges at the meeting point between the floor plate and the external wall. The simulation of the variants assumed an 8 cm thick internal insulation of calcium silicate panels. As this refurbishment variant is already problematic in the case of low soil moisture only the results for the case with low soil moisture are given. None of the recommended refurbishment variants with internal insulation can be rated as functional. Using the boundary conditions and insulation thicknesses described here even in the case of low soil moisture there is a high risk of damage. It is clear that hygrothermal simulations are indispensable for such constructions because the preliminary design process cannot assess the potential for damage. In many cases it is necessary to vary the thickness and type of insulation in order to arrive at an agreeable result. The correct choice of the insulating material is ultimately decisive for the functioning of the internal insulation. Vaporproof insulating materials such as foam glass can be helpful. However, in almost every example of internal insulation it is necessary to transect or damp-proof the vertical masonry. The problem of internal insulation is already extensively discussed in the chapter: “Internal insulation and the built-in heads of timber beams”. A detailed description of the design principles and the provision of evidence can be found in [Wegerer 2010]. Help can also be found in the WTA Bulletin 6-4, which describes the design process and the most influential parameters for internal insulation systems.

Relative air humidity and temperature patterns during the course of a year Figs. 52 and 53 show a comparison of the relative air humidity and temperature patterns during the course of one year at the internal corner between the internal plaster to the external wall and the floor for the investigated refurbishment variants when a steady state has been reached (50th year of simulation).

Low soil moisture

Fig. 52: Relative air humidity and temperature in the internal corner between the internal plaster of the external wall and the top of the floor finish in the case of low soil moisture when a steady state has been reached

Course of a year

In the case of low soil moisture, only the variant with internal insulation is problematic in that the pore air humidity is slightly above 80 % for the entire year. All other refurbishment variants have a reduced level of relative humidity than the existing construction and significantly higher surface temperatures in the corner in winter. There is hardly any variation in the surface temperatures of the different variants with external insulation. Regarding the position of the floor insulation in the variants with external insulation the variant with the insulation to the underside of the floor has a slightly lower level of relative humidity than the variant in which the insulation is on the upper side. In the case of high soil moisture, the relative humidity in the internal corner rises above 80 % for the entire year. Only umbrella insulation without floor insulation significantly improves the moisture behavior in the internal corner in comparison with the existing construction. In this case it is just possible to avoid the formation of mold on internal mineral-based surfaces. Risk can be minimized by an underfloor heating with thickly laid and extra heatable edge strips. An alternative would be the use of component heating. However, it is recommended that this risk is only taken in connection with detailed design work, the measurement of the moisture content in the existing building and the introduction of passive measures (adaptation of internal plaster, alkaline paints and good corner ventilation). All other refurbishment measures are unsuitable which means that in such cases the dampproofing of the vertical masonry is unavoidable.

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Basics

High soil moisture

Course of a year

Fig. 53: Relative air humidity and temperature in the internal corner between the internal plaster of the external wall and the top of the floor finish in the case of high soil moisture when a steady state has been reached

Temperatures are lower in comparison with the variants with low soil moisture. For more on the loss of heat energy through the uninsulated floor plate see “Synopses and conclusions” below.

Synopsis and conclusions Most buildings without cellars that were built before the 1950s in Central European climates have no dampproofing in the vertical masonry rising from the ground. Depending upon the degree of moisture of the surrounding soil this can lead to problematic moisture behavior in the internal corner between the external wall and the floor which is sitting directly on the earth. In the case of low soil moisture all refurbishment variants with highly thermally insulated façades (including perimeter insulation down to the bottom of the foundation) increase surface temperatures and, hence, improve the moisture behavior at the internal corner. The refurbishment variant with internal insulation is, on the other hand, problematic: This refurbishment variant should only be tackled with an experienced building physicist and must involve the in situ measurement of the actual humidity situation and the development of individually adapted insulating measures. The combination of vaporproof internal insulating materials, a moderate external climate, low soil moisture and excellent execution can lead to an acceptable solutions. In the case of high soil moisture, the existing variant is already highly critical in terms of the formation of mold on internal surfaces. Only an umbrella insulation (external insulation plus perimeter insulation and an uninsulated floor) can lead to a significant improvement of the moisture behavior. All other refurbishment variants can only be realized in parallel with the creation of a damp-proof course in the vertical masonry! Naturally the decision not to thermally insulate the floorplate leads to increased heat loss and, hence, increased heating demand. The level of this extra loss compared with the variants with an insulated floorplate depends principally on the compactness of the building and the characteristic floorplate dimensions (EN ISO 13370): Deep rooms and dense building forms lead to relatively low losses via the floor. In addition to this, the composition of the soil (gravel, cohesive soil, rock) determines its thermal conductivity and the transmission losses via the floorplate. The presence of groundwater can also be significant, above all when the flow rate is relatively high. In any case, the perimeter insulation (umbrella insulation) should have a depth of at least 1 m and, better, 1.5 m. This can also be laid horizontally in the case of a building with a very flat foundation. This additional insulation can be financed via the savings resulting from not having to renew the floor or transect the masonry. As a whole, the execution of an umbrella insulation without floorplate insulation to passive house or EnerPhit standards and in combination with the mentioned boundary conditions and risk-minimizing strategy represents an optimal strategy for protecting against moisture and reducing transmission losses at an acceptable cost. In all cases, the appraisal of the existing and the design of the new must be carried out with great care. Solutions with external insulation and floorplate insulation are only suitable for situations with relatively low soil moisture. Otherwise the masonry must be transected by a damp-proof course.

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Basics Internal insulation and the built-in heads of timber beams Special challenges with internal insulation caused by timber beams built into masonry walls The design of internal insulation The internal insulation of external constructional elements increases the linkage between the existing construction and the external climate. The following problems can lead to the formation of mold, the destruction of materials and flaking due to frost: • Formation of condensation on the cold side of the internal insulation • Formation of frost on building elements containing water in the external wall Hence, the design and execution of long-term, damage-free internal insulation and the adjacent existing construction must take into account the following factors: • The building physics characteristics of the existing building element: thermal conductivity and, in particular, the potential for moisture to be carried by diffusion or capillary action, building materials whose consistency is endangered by increased moisture levels (e.g.: brick masonry or trusses), etc. • Insulating system: thickness of insulation, thermal conductivity and behavior in humid conditions (water vapor diffusion, capillary conductivity, storage of moisture) • Local climate (e.g. intensity of driving rain, solar radiation, external air temperatures) • Characteristics of the external constructional layer (vapor diffusion of the external finish, water absorption capacity, color and, hence, degree of absorption of solar radiation) • Internal air conditions (possible presence of comfort ventilation, uses with long-term high levels of ambient humidity such as laundries) • Critical connecting points (e.g. connection between internal walls and floors (heads of timber beams), corners of buildings) In all cases it is urgently recommended to request a building physicist to analyze the situation or even to carry out a moisture simulation. When designing the internal insulation of a building with existing timber beam floors, particular attention must be paid to the hygrothermal behavior of the beam heads built into the masonry due to the fact that it is this timber in this area that cools most strongly. If convection currents also result in warm, humid internal air reaching this building element, this can lead to increasing levels of wood moisture on the supporting surfaces of these beam heads and, hence, to decay. State-of-the-art of the design of internal insulation and the built-in heads of timber beams In line with the general technical rules the condensation-free status of internal insulation is currently verified by the Glaser method or, ideally, calculated in one or two-dimensions using a hygrothermal simulation program. However, this approach does not adequately estimate the risk of damage. There is no standard proof that can guarantee the design of connecting details and, in particular, the details of the connection of the head of the timber beam. The design guidelines [WTA 2009/D] qualitatively set out all key physical processes which are to be taken into account when designing internal insulation. The problematic of timber beam heads is included as an example of complex connections: “uninsulated reveals to windows and external doors and complex connections (e.g. beam heads) are endangered by the fall in temperature given that here the thermal insulation is in any case reduced due to the constructional situation. Such areas are thus to be considered more closely.” There is, however, a complete lack of clear design recommendations. [AkP32 2005], [Feist 2012a], [Loga 2003], [Müller 2011], [Ruisinger 2011], [Wegerer 2012] present numerous test buildings and objects which demonstrate functioning but defective internal insulation, some in combination with timber beam floors. The danger of moisture reaching the cold face of the internal insulation due to convection is often discussed in the literature but no publication has yet set out a model for guaranteeing air flow to floor cavities or the supporting surfaces of timber beams. [Wegerer 2012], however, shows that, when examining this critical detail, the study of air flow and the carrying out of a three-dimensional hygrothermal simulation are unavoidable. Programs that permit three-dimensional air flow to be considered are currently still in the development phase. Hence, the examples presented below can only be described as the findings of current research. They present a model for taking air flows into account when calculating the connections of internal insulation with floors and suggest possibilities for providing proof. Due to the fact that the variation of individual input parameters produces a broad range of results the details examined below should not be uncritically regarded as design requirements. The results of the calculations are only valid for the idealized boundary conditions assumed here. Rather, they should underline the need for further investigatory and research work into, in particular, three-dimensional hygrothermal simulation and the calculation of convective moisture permeation. Contrary to many opinions expressed in the literature set out below the following analysis of results of simulations shows that the design of internal insulation of buildings with timber beam floors is still in the “experimental phase” and does not represent standard details. All projects addressing this theme should be regarded as “test projects” and should be accompanied by researchers.

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Basics The calculations set out below show that the provision of evidence regarding timber beam connections requires the consideration of certain boundary conditions which are to be recorded during design. This is necessary for each individual object given that each building has a range of individual, project-specific boundary conditions. In order to be able to provide generally valid evidence regarding the durability of a timber beam connection all input quantities must be statistically processed. All input for a hygrothermal simulation is to be expressed with distribution functions. This data permits the calculation of the failure probability of the construction – as a form of probabilistic safety concept. Other safety concepts such as limiting load analysis in structural engineering should also be adopted.

Methods for hygrothermal investigations Critical hygrothermal conditions The time-dependent penetration of moisture into building materials and the external temperatures which arise play a key role in determining the life a building element. This moisture penetration can be triggered by a range of processes. • Internal climate: The use of rooms usually means that internal air is significantly more humid than external air. Convective air flow in building elements results in warm, humid air reaching constructional elements which have lower temperatures. The end of a beam head reaches a certain temperature determined by the thickness of the masonry and, hence, the external cover to that beam head. There is a direct relationship between this temperature and the dew point at this location (more details are given in [Stopp 2010] and [Gnoth 2005]). Hence, it is possible to avoid condensation at a beam head by keeping above a minimum temperature or avoiding convective air flow into the building element. • Driving rain on façades: This is not initially considered in the following analyses given that moisture permeation due to driving rain is heavily affected by concrete local characteristics (location, position of the area of wall, air-flow around the building, façade detailing, cornice, roof projection, etc.) and the capacity of the external plaster to absorb water. • Moisture penetration in the existing construction and the entry of rainwater during building: These are not considered in this analysis. The results are only applicable if it can be shown that a waterproof external plaster ensures that no rainwater is absorbed and that any humid masonry resulting from the building phase has already dried out. • Damp rising from the ground: This is not considered in this analysis. Masonry can absorb water depending upon the groundwater situation and ground conditions, rainwater seepage and the existence of any waterproofing. • Damage to water-carrying pipework: This is not considered below. Critical hygrothermal conditions are related to a range of damage mechanisms: • Given suitable growing conditions, mold can grow on the surface of or inside constructional elements. This analysis addresses the risk of constructional elements being affected by mold due to time-related temperature and moisture conditions. This process will use the algorithm [Thelandersson 2009] in order to determine the number of days with such growing conditions • Wood-destroying fungi can grow if certain temperature and humidity levels persist for certain lengths of time and this can lead timber to lose mass and, then, stability. This process is modeled mathematically in [Viitanen 1996]. Based on this model [Kehl 2013] gives the critical pore air humidity for each temperature. This approach permits the simple evaluation of the simulation results. • The influence of moisture level on the thermal conductivity of building materials is taken into account in the calculations. The following risks of building materials being destroyed are not covered in this analysis: • Hygrothermal changes in length and the related internal tensions • The development of ice in cavities or porous building materials • The growth of algae on external façades • Variables other than temperature and humidity which influence the growth of mold Leaks Leaks are small imperfections in the airtightness of a construction. These small imperfections can occur when, for example, small folds arise during the gluing of film or layers are pierced by fixing materials. Drills and similar tools can also create leaks which enable air to enter the construction. There are no established findings regarding changes in local airtightness due to wind-induced building movement, the swelling and shrinking of timber building elements or the aging of adhesive connections.

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Basics Analogous to ÖNORM EN 12114:2000 [ÖNORM EN 12114], leaks can be characterized with the following equation by the coefficient C and an exponent n:

.

m mass flow rate (air) in kg/m² s C air volume flow coefficient in m³/m² s Pan ∆p pressure difference in Pa n leak exponent (without dimension) ρ air density kg/m³ The equation describes the mass flow rate of the air entering the element for each m² of area and is dependent upon the pressure difference between the interior and exterior. Even if the airtight layer is carefully executed and all connections are carried out in line with the latest technical standards minimal leaks will result. Hence, no example of a perfectly airtight (leak-free) layer was investigated because this does not occur in practice. The following simulations differentiate much more often between “minimal” and “typical” leaks. In the following sections an execution with minimal leakage defines a construction with minimal air flow. According to [Bednar 2013] this can be described with

In the case of an execution with typical leakage, the average air flow can be defined with:

The typical leakage case corresponds to a situation in which every square meter of the surface of the element has one hole with a diameter of around 2.6 mm (calculated in line with [Hagentoft 2001]). Execution variants for the internal insulation The wide range of alternative methods for executing internal insulation can be reduced to two principal variants for the detailing of a timber beam connection: internal insulation which ends at the floor and ceiling and, hence, fails to create a continuous heat-insulating and airtight layer (“room-by-room internal insulation”) and internal insulation which continues through the floor (“continuous insulation”). This continuous insulation is only interrupted where the heads of the timber beams enter the masonry and creates a continuous airtight layer to the inside of the insulation. In both cases the floor construction retains its original form. If continuous internal insulation is executed this requires the opening up of the floor adjacent to the wall. The ballast, floor construction, ceiling, lintel formwork and surface plastering remain untouched. Both variants are shown in Fig. 54. In the performed simulations there are various ways in which moisture can reach the beam head where it can lead to critical hygrothermal conditions. These primarily include diffusion and convective air flow (e.g. due to leaks in the vapor barrier). It is also possible that humidity from the ambient air enters the ceiling cavity and then reaches the supporting surfaces of the beams due to the circulating air movement generated by the temperature difference between the ceiling and the floor finish. In technical terms, room-by-room internal insulation represents the simplest solution for thermal refurbishment using internal insulation. As the section in Fig 54 (Variant 1) shows, there is a connection between the floor cavity and the air space around the beam head (continuous void). Humidity from the floor cavity can reach the beam head and the cold masonry (blue arrow). This will create more critical humidity conditions than in the existing construction. If a number of apartments on adjacent floors are thermally refurbished using internal insulation during a general refurbishment project it makes sense - for reasons of both energy efficiency and the long-term stability of the construction – to apply continuous insulation across a number of stories. This will create a vapor barrier between the air space around the beam head and the floor cavity. This means that two separate circulating air movements are created which ensure that no humidity exchange can take place as a result of thermally induced convection. Basic parameters and assumptions Constructions The existing construction which is investigated in detail consists of masonry with a 44 cm thick masonry wall (format of old Austrian bricks 14 × 29 × 6.5 cm) plastered on both sides. The beam is 20 cm high and 16 cm wide. The floor construction above the lintel formwork consists of 8 cm of ballast and a sub-floor and timber flooring, each with a thickness of 2 cm. The floor cavity and the air space around the beam head are connected, which means that humidity diffusing in the floor cavity can reach the beam head.

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Basics

Variant 1 room-by-room insulation continuous void



1,5 cm 44,0 cm 1,5 cm 5,0 cm 1,0 cm

External plaster Masonry Internal plaster Multipor Plaster

2,0 cm 2,0 cm 8,0 cm 2,0 cm 20,0 cm 2,0 cm 1,5 cm 1,0 cm

Timber flooring Sub-floor Ballast Timber formwork timber beam / air Timber formwork Stucco Lime plaster

Variant 2 continuous insulation separated voids (beam head/cavities)

1,5 cm 44,0 cm 1,5 cm 5,0 cm 1,25 cm

External plaster Masonry Internal plaster Mineral wool Vapor barrier Plasterboard

2,0 cm 2,0 cm 8,0 cm 2,0 cm 20,0 cm 2,0 cm 1,5 cm 1,0 cm

Timber flooring Sub-floor Ballast Timber formwork timber beam / air Timber formwork Stucco Lime plaster

Varpor barrier

Void Void Varpor barrier

Fig. 54: Ceiling connection detail with ‘room-by-room’ (left) and continuous (right) internal insulation, above: vertical section through axis of beam, below: horizontal section through axis of beam

A system using mineral wool, a vapor barrier (sd = 100 m) and plasterboard was chosen for the continuous internal insulation. The room-by-room internal insulation was executed using calcium silicate panels. As this is a capillary active insulating material there is no need to lay a vapor barrier. The connection between the voids leads to more critical moisture conditions than in the case of continuous internal insulation. However, this is due not to the choice of insulation but to the basic constructional detailing of the two variants. Material and surface characteristics The material parameters (density, diffusion resistance etc.) and the material functions (moisture storage function, suction tension curve etc.) are based on the Masea database of the Fraunhofer Institute for Building Physics [Masea 2015] or on data provided by the manufacturers. The calculations also take account of the anisotropy of wood in connection with thermal conductivity and diffusion resistance It was assumed that the external surface is west-facing, the degree of solar absorption is 0.5 and the degree of emission is 0.9. Simplified illustration of the constructions The existing construction and internally insulated variant were somewhat simplified for the dynamic calculations. The model illustrating the area between the axis of the beams and the axis of the cavity was input in three dimensions in order to permit the most realistic simulation possible of the moisture conditions arising at the beam heads. All models considered the beam over a length of 4.50 m. As the given length of the cavity influences the amount of moisture transported a realistic simulation requires the choice of a length which roughly corresponds to a normal room depth.

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Basics Cell dimensions The input of information into the simulation program requires the division of the model into cells. The finer the grid, the more precise the results of the calculations. In order to reduce the duration of the simulation a cell dimension of around 3 cm was chosen. In areas with increased temperature and humidity gradients (e.g. the internal insulating layer) smaller cell widths (1 cm) were input.

Leaks Parameters C and n were selected as given in section leaks. The air volume flow coefficient C which is required for the calculation of the mass flow rate in the building element refers to an area of building element in m², given that this defines the size of the resulting leak per m² of the surface where it could potentially arise. In the case of the existing construction and room-by-room internal insulation the ceiling and the floor finish of the floor are used. In the case of continuous internal insulation the area of the vapor barrier is used.

Condensation source (green)

HAM4D_VIE – the chosen simulation tool – offers various possibilities for considering convective moisture permeation via leaks. In this case this was modeled via a source of condensation on the vertical masonry surface behind the beam head. The quantity of condensation occurring on the defined surface is determined by the mass flow rate from the interior space into the construction and the temperature conditions on this surface.

Fig. 55: Location of the condensation source

External climate Figure 56 shows the average monthly temperatures of various locations in Germany and Austria. An internal insulation system is more critical during lower winter temperatures because more condensation occurs on the layer between the existing construction and the newly applied insulation. It can be seen that Klagenfurt is a location with very low temperatures in winter and hence, is a representative case for Austria. Usually, when structures in Austria are not designed for a specific location the climate of Klagenfurt is used in order to test them for durability. The long-term average monthly values for Klagenfurt (test reference years (TRY) from the period between 1991 and 2005) were used [Haas 2012]. However, in order to evaluate the durability of structures it is not critical enough to apply long-term average climatic values. In comparison with the long-term average value the average value across a decade can be up to 2 kelvins lower in January and up to 1 kelvin lower in July. In cases of the threat of condensation in winter the ÖNORM EN 15026 (“Thermal and humid behavior of buildings and building elements – evaluation of moisture transfer by numerical simulation”) also recommends that a moderately critical climate data set should be made even more critical by reducing the temperature values by – 2 kelvins. (TRY – 2).

Average monthly temperature in °C

Fig. 56: Long-term average monthly external temperatures in January for locations in Germany and Austria. Source: Germany: http://www.klimadiagramme.de/ttnn.html, Austria: http://www.bmwfj.gv. at/hp/klimadatenbank/Seiten/klimadaten. aspx

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Altitude in m

Details of Passive Houses: Renovation

Basics Internal climate The following simplified internal climatic conditions are used for the dynamic calculation: Operational temperature in °C

Time in hours

Relative internal air humidity

Time in hours

Fig. 57: Chronological sequence of the internal air temperature and internal radiation temperature (above) and the relative humidity of the internal air (below)

Due to the leaks in the structure the pressure difference between the internal and external air and also between the various levels of a building is important for the air flow. The calculations were carried out with an internal excess pressure of 2 Pa in winter and 0 Pa in summer.

Positive internal air pressure in Pa

Time in hours

Fig. 58: Assumed positive pressure between internal and external air

This minimal pressure difference results from the assumption that leaks occur in any case with a height difference of one story (4–5 m in the case of late nineteenth century buildings) and, similarly, that there is a temperature difference of 20 kelvins in January [Hagentoft 2001]. If there are large interconnected spaces inside a building (atria, staircases etc.) even larger pressure differences and considerably more air flow can arise. However, even in this case the resulting pressure differences are strongly dependent on the airtightness of the building envelope in the living space (windows etc.).

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Basics Limiting value for wood moisture In order to evaluate the results the most important question is whether the resulting moisture at the beam head leads to decomposition and, hence, to a loss of mass or stability which will eventually effect the load-bearing capacity of the construction Some norms, such as [DIN 68800-1], give a wood moisture limiting value of 20 M.-% in order to definitely exclude all possibility of the decomposition of wooden elements. A series of experiments (e.g. in [Viitanen 2010]) has, however, shown that this limiting value upon which wood can start to decompose is dependent upon temperature. [Kehl 2013] also gives a limiting temperature-related value for pore air humidity (in %) in the investigated building elements, below which moisture conditions are not critical. This lies between 95 % at 0 °C and 86 % at 30 °C (with a straight line between) and corresponds with a wood moisture between 26 (0 °C) and 20 M.-% (30 °C). WTA Bulletin 6-5 (Internal insulation in line with WTA II: Proof of internal insulation systems by means of numerical calculation procedures) [WTA 2014] also mentions this approach. In all models, the significant point of evaluation is the external cell at the upper end of the beam head because it is this cell that has the highest moisture content of all the edge cells. Evaluation of the results The moisture level is basically evaluated in terms of air humidity (pore air humidity). Hence, the results in the following tables are colored differently in line with the danger that they represent: According to the chosen approach the risk of failure at normal temperatures is very small up to a maximum relative air humidity of 85>% (green). When the maximum relative air humidity lies between 86 and 90 % (yellow) detailed work is required to prove that the construction remains free of danger. If maximum relative air humidity exceeds 90 % (red) it can be assumed that there is a very high risk that the construction will fail. The maximum relative air humidity set out in each of the following tables was based on the final year of the simulation. This was generally the point at which a steady state had been reached (in which the periodic application of a climate data set to the construction failed to change the long-term moisture level). In cases when it was clear that no steady state with an acceptable level of humidity in the wood would arise the simulation was finished early. This explains why in certain cases – such as, for example, the use of TRY +2 – more critical relative air humidities were given than in the use of TRY, despite the fact that this case must be non-critical due to the combination of a higher external temperature with the same internal climate. This approach is more precisely evaluated in [Kehl 2013]. Here, the steady state relative air humidity and temperature in the investigated cells over the course of a year were used to calculate the number of days in which critical conditions were present that could cause the wood to disintegrate. Simulation variants In addition to variants with a particularly critical external climate (test reference year for Klagenfurt –2 kelvins) simulations were also carried out for all constructional variants using a standard test reference year and a test reference year of +2 kelvins. In order to be able to guage the risk of damage in a concrete refurbishment project using the investigations carried out in this work one of three external climates can be applied to a location based on, for example, the annual average temperature. The following variants of an existing structure and room-by-room internal insulation are investigated: 1) Beam head surrounded by air, minimum leakage (minimum air flow) 2) Beam head surrounded by air, typical leakage (average air flow) 3) Beam head surrounded by ballast (no void), result: minimum leakage (minimum air flow) In the case of the existing construction an execution with minimum leakage means that internal air can enter the floor cavity via, for example, cracks or holes drilled in the ceiling and reach the beam head due to the air movement caused by the pressure difference between the external and internal areas In the case of continuous insulation the following variants were investigated: 1) Vapor barrier with minimum leakage (minimum air flow) 2) Vapor barrier with typical leakage (average air flow) For a detailled summary of the simulation parameters refer to www.ibo.at/PH_SAN

Results Existing construction In the case of execution with minimum leakage the existing construction largely shows an unproblematic level of wood moisture.

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Details of Passive Houses: Renovation

Temperature in °C

Relative internal air humidity

Basics

Time in years

Fig. 59: Existing construction, minimum leakage (minimum air flow), TRY

When using the TRY Klagenfurt and a relative air humidity in the adjacent room between 50 and 65 % a maximum of 86.4 % relative air humidity is reached and yet, according to [Kehl 2013], this does not represent critical humidity conditions. Only a particularly critical climate based on TRY – 2 kelvins and 50–65 % relative air humidity can lead to timber decay (see Fig. 60a).

Timbe r

TRY

TRY +2 K

76.6

74.6

71.6

40–65 %

81.9

79.8

76.7

50–65 %

89.4

86.4

82.3

Existing construction – airtight – TRY –2 decay

decay

possib

le

not p

ossib

le

Limiting value

Relative internal air humidity

Temperature in °C

Timbe r

Timbe r

Relative internal air humidity

Relative internal air humidity

Internal climate

Timbe r

TRY –2 K

30–65 %

Timbe r

Timbe r

Tab. 5: Existing construction (minimum leakage), maximum recorded pore air humidity in %

Existing construction – airtight – TRY decay

decay

possib

le

not p

ossib

le

Limiting value

Temperature in °C

Existing construction – airtight – TRY +2 decay

decay

possib le not p ossib

le

Limiting value

Temperature in °C

Fig. 60a–c: Evaluation of the moisture level in line with, existing construction, minimum leakage [Kehl 2013]

Details of Passive Houses: Renovation

Fig. 61: Existing construction, minimum leakage, TRY, internal climate 30–65 %, maximum relative air humidity in steady state (hour 17,823)

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Basics

Temperature in °C

Relative internal air humidity

In the case of an execution with typical leakage the moisture conditions are, as expected, more critical. There is very high relative air humidity in two cases, in the yellow case an evaluation by the model from [Kehl 2013] poses no danger (Tab. 6).

Time in years

Fig. 62: Existing construction, typical leakage (average air flow), TRY

Internal climate Tab. 6: Existing construction (typical leakage), maximum recorded pore air humidity in %

TRY –2 K

TRY

TRY +2 K

30–65 %

76.7

74.7

71.6

40–65 %

84.6

81.0

77.1

50–65 %

97.7

92.4

86.7

Existing construction – not airtight – TRY

Timbe r deca y pos Timbe sible r deca y not possib le

Limiting value

Relative internal air humidity

Relative internal air humidity

Existing construction – not airtight – TRY –2

Timbe r deca y pos Timbe sible r deca y not possib le Limiting value

Temperature in °C

Temperature in °C

Relative internal air humidity

Existing construction – not airtight – TRY +2

Fig. 63 a–c: Existing construction, typical leakage, evaluation of the moisture content in line with [Kehl 2013]

Timbe r

Timbe r

decay possib le decay not p ossib le

Limiting value

Temperature in °C

In the case of the test reference year the simulations of the variants in which the area around the beam head were filled with ballast were also evaluated.

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Details of Passive Houses: Renovation

Temperature in °C

Relative internal air humidity

Basics

Fig. 64: Existing construction, minimum leakage (ballast), TRY

Time in years

Internal climate

TRY

30–65 %

63.8

40–65 %

68.0

50–65 %

73.4

Tab. 7: Existing construction, minimum leakage (ballast), TRY, maximum recorded pore air humidity in %

Room-by-room internal insulation

Temperature in °C

Relative internal air humidity

In the case of room-by-room internal insulation the combination of a fall in the temperature in the external wall and the retention of the air connection between the floor cavity and the beam head can lead to particularly critical conditions.

Fig. 65: Room-by-room internal insulation, minimum leakage (minimum air flow), TRY

Time in years

Fig. 66: Room-by-room internal insulation, minimum leakage, TRY, internal climate 30–65 %, maximum relative air humidity in steady state (hour 28,117)

Internal climate

TRY

30–65 %

74.8

40–65 %

82.1

50–65 %

89.7

Tab. 8: Room-by-room internal insulation, minimum leakage (ballast), TRY, maximum recorded pore air humidity in %

Even in the case of execution with minimum leakage (minimum air flow) only low levels of air humidity in winter can avoid the creation of critical conditions. Only the cases TRY +2 kelvins/30–65 % and TRY/30–65 % can be considered as unproblematic. In the case of execution with typical leakage problematic moisture conditions arise in virtually all investigated variants.

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Basics In the case of the variant in which the area around the beam head is filled with ballast there are much better results because there is no longer an air connection between the floor cavity and the beam head. However, in the case with an internal climate of 50–65 % relative air humidity there is still no steady state after seven years and humidity continues to increase. Continuous internal insulation

Temperature in °C

Relative internal air humidity

The separation of the floor cavity from the void around the beam head results in very low levels of relative air humidity, especially in the case of the variant with minimum leakage.

Fig. 67: Continuous internal insulation, minimum leakage (minimum air flow), TRY

Time in years

Internal climate Tab. 9: Continuous internal insulation (minimum leakage), maximum recorded pore air humidity in %

TRY –2 K

TRY

TRY +2 K

30–65 %

72.7

73.3

67.3

40–65 %

79.0

76.9

72.3

50–65 %

82.8

82.4

78.0

Timbe r

decay

decay

possib le not p ossib

le

Limiting value

Relative internal air humidity

Temperature in °C

Timbe r

Timbe r

Relative internal air humidity

Relative internal air humidity

Mineral wool – airtight – TRY –2 Timbe r

Timbe r Timbe r

Mineral wool – airtight – TRY decay

decay

possib

le

not p

ossib

le

Limiting value

Temperature in °C

Mineral wool – airtight – TRY +2 decay

decay

possib

le

not p

ossib

le

Limiting value

Temperature in °C

Fig. 68a–c: Continuous internal insulation, minimum leakage, evaluation of moisture levels in line with [Kehl 2013]

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Fig. 69: Continuous internal insulation, minimum leakage, TRY, internal climate 30– 65 %, maximum relative air humidity in steady state (hour 20,869)

Details of Passive Houses: Renovation

Basics

Temperature in °C

Relative internal air humidity

In the case of execution with typical leakage, much more critical moisture conditions arise. In the case marked in yellow (TRY/30–65 %) according to [Kehl 2013] there is no moment at which critical conditions arise which could lead the wood to decompose (Tab. 10).

Time in years

Fig. 70: Continuous internal insulation, typical leakage (average air flow), TRY TRY –2 K

TRY

TRY +2 K

30–65 %

91.2

86.9

78.6

40–65 %

98.8

95.6

90.7

50–65 %

99.2

98.4

98.7

Timbe r

Timbe r

decay

decay

possib

le

not p

ossib

le Limiting value

Mineral wool – typical leakage – TRY –2

Relative internal air humidity

Temperature in °C

Timbe r Timbe r

decay

decay

Relative internal air humidity

Relative internal air humidity

Internal climate

Tab. 10: Continuous internal insulation (typical leakage), maximum recorded wood moisture in M.-%

Timbe r deca Timbe y pos r deca sible y not possib le

Limiting value

Mineral wool – typical leakage – TRY Temperature in °C

possib

le

not p

ossib

le

Limiting value

Mineral wool – typical leakage – TRY +2 Temperature in °C

Fig. 71a–c: Continuous internal insulation, typical leakage, evaluation of the moisture levels [Kehl 2013]

Heating of beam heads If a simulation results in high moisture levels at the beam head this can mostly be traced back to the low surface temperatures at the beam head which lead to condensation when warm, humid internal air reaches this area. One way of avoiding this is to heat the timber beam at its head. In HAM4D_VIE this can be achieved by integrating a heat source (e.g. heating pipe) into the construction. As soon as a sensor records that the temperature has fallen below a predetermined level the heat source

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Basics is activated and heats at a predefined constant temperature. If the temperature at the sensor rises back above the given minimum level the heat source switches itself off again. The model with continuous internal insulation and with the most critical boundary conditions (TRY –2 kelvins, relative internal air humidity 50–65 %, with leakage) was used to demonstrate the effects of heating the beam head. The results were compared for two different positions for the heat source (above or below the beam head, see Fig. 25). The minimum temperature at the sensor was always given as 15 °C and the heating temperature in all variants was 30 °C. The level of this necessary minimum temperature is dependent upon the dew-point of the ambient air. For an air temperature of 22 °C and 50 % relative air humidity in winter the temperature should not be allowed to fall below 11.1 °C [Bednar 2013].

Above beam

Fig. 72: Model with continuous internal insulation, points for the evaluation of the heating of the beam head

Below beam

Fig. 73: Model without heating

Fig. 74: Heating with a heating pipe at the level of the skirting board (blue: sensor, green: heat source)

Fig. 75: Heating with a heating pipe below (blue: sensor, green: heat source))

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Basics

Fig. 76: Heating of the masonry (blue: sensor, green: heat source)

Fig. 77: Heating with heating pipes above and below (blue: sensor, green: heat sources)

Figs. 73 to 77 (left) show the location of the sensor and the heat source. The diagrams to the right show the temperature field of the construction at the moment at which the beam head has reached its lowest temperature in the variant without heating (Fig. 20) (hour 8,892). In Fig. 74 it can be seen that a heating pipe in the chosen position (level of the skirting board) cannot provide enough heating power to adequately heat the underside of the beam. This can also be seen in the results for relative air humidity in Figs. 78 and 79: In both variants the relative air humidity is lower than in the unheated variant but the buildup of moisture is only delayed. The same is true for a heating pipe positioned below the beam (see Fig. 75).

without heating heating below heating skirting board heating above + below heating masonry

Time in years

Relative internal air humidity

Relative internal air humidity

Heating the masonry can bring a targeted reduction in the buildup of condensation (Fig. 76). Similarly, the relative air humidity can be held stable at a non-critical level by the positioning of two heating pipes (one above and one below the beam head, Fig. 77).

without heating heating below heating skirting board heating above + below heating masonry

Time in years

By varying the minimum temperature (at the sensor), the heating temperature and location of the heat source, an optimal combination can be created.

Figs. 78 + 79: Results for the evaluation point above the beam (left) and below the beam (right)

Fig. 80 shows the total heat energy required by a beam head during a year in the case where the masonry is heated. Fig. 81 shows the total heat required for the variant with two heating pipes.

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Total heating volume in kWh

Total heating volume in kWh

Basics

Time in months

Time in months

Fig. 80: Heating of the masonry, total heating volume required for the heating of a beam head during one year. Fig. 81: Heating with pipes above and below the beam, total heating volume required for the heating of a beam head during one year (total for both pipes)

In very critical climatic boundary conditions heating is necessary both above and below the floor. If one relates the cost of this heating to the usable space (assumed room depth 5 m), this gives an additional heating cost of around 12 kWh/m²a, although part of this heating also directly benefits the space. If one compares this cost with the potential savings produced by the internal insulation, it is to be expected that these potential savings will be reduced by around 20 %, depending upon the height of the space. The influence of orientation In order to be able to estimate the influence of the orientation of the façade on the moisture content in the beam, simulations were carried out with a northern orientation. In this case the air temperature and relative air humidity remain the same as the western orientation but the solar radiation striking the building element is reduced. This leads to a reduction of the temperature level within the building element and slows the drying process. As in previous simulations driving rain is not entered as a boundary condition.

West without driving rain North without driving rain

Fig. 83: Comparison of pore air humidity at western and northern orientations without driving rain (model with roomby-room internal insulation, not airtight, TRY, internal climate 40–65 %)

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West without driving rain North without driving rain

Time in years

Time in years

Fig. 82: Comparison of pore air humidity at western and northern orientations without driving rain (model with continuous internal insulation and leakages, TRY, internal climate 40–65 %)

Relative internal air humidity

Relative internal air humidity

In the case of a northern orientation the moisture content is somewhat higher than the value calculated for a western orientation. Figs. 82 and 83 show the results for construction based on room-by-room and continuous insulation. The simulation used the climate for the test reference year (TRY) in Klagenfurt together with an internal climate of 22–26 °C/40–65 % relative air humidity.

Influence of driving rain Driving rain was not considered in previous simulations because this is strongly dependent upon the concrete constructional situation (capacity of the plaster to absorb water, airflow patterns etc.) and will create a range of variants in combination with other boundary conditions (internal climate, airtight/not airtight, etc.) which, ultimately, are insignificant. In addition to this, it is generally recommended that a façade is rendered water-repellent when internal insulation is applied due to the fact that even an on-site determination of the coefficient of water absorption fails to guarantee that the same value applies to the entire façade. The result can be increased local absorption of water due to cracks in the plaster, etc. For purposes of comparison, however, several simulations with driving rain were carried out. The coefficient of absorp-

Details of Passive Houses: Renovation

Basics tion of water of the façade was assumed to be 5 kg/m²h1/2, which is a standard value for lime plaster [Bednar 2000].

Relative internal air humidity

In all investigated variants (existing construction, continuous internal insulation, room-by-room internal insulation) the results with and without driving rain – in the presence of average airflow (with leakages) – are more or less identical (see Fig. 84).

With leakage without driving rain Without leakage without driving rain With leakage with driving rain Without leakage with driving rain

Time in years

Fig. 84: Comparison of pore air humidity with/without driving rain and with/without leakage (model with continuous internal insulation, with leakages, TRY, internal climate 40–65 %)

The condensation at the beam head resulting from convective air flows from the internal space means that the masonry has a higher basic moisture content. The increase of the moisture content as a result of driving rain can thus be ignored when compared with this increase in the moisture content due to condensation (see Fig. 85). If, however, minimum air flow is assumed (without leakages), the moisture load due to this condensation on the masonry is reduced. Hence, in this case the driving rain has a visible effect on the result.

Fig. 85: Development of pore air humidity after rain, with leakages (left: without driving rain, right: with driving rain) Increase in the moisture content in driving rain in peripheral cells

Fig. 86: Development of pore air humidity after rain, without leakages (left: without driving rain, right: with driving rain)

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Basics Summary of the results The following tables show an estimate of the necessary degree of design and execution for the various constructional situations and external climates. RH in %

Existing construction minimum leakage

Room-by-room internal insulation continuous cavity

typical leakage

minimum leakage

typical leakage

Continuous internal insulation separate cavity minimum leakage

typical leakage

TRY Klagenfurt –2 K (av. annual temperature: 6.7 °C). max. recorded wood moisture in M.-% 30–65 76.6 76.7

90.1 95.3

72.7 91.2

40–65

81.9

84.6

96.0

99.1

79.0

98.8

50–65

89.4

97.7

97.0

99.3

82.8

99.2

TRY Klagenfurt (av. annual temperature: 8.7 °C). max. recorded wood moisture in M.-% 30–65 74.6 74.7

85.6 89.6

73.3 86.9

40–65 79.8 81.0

94.3 96.8

76.9 95.6

50–65 86.4 92.4

94.7 99.1

82.4 98.4

TRY Klagenfurt +2 K (av. annual temperature: 10.7 °C). max. recorded wood moisture in M.-% 30–65 71.6 71.6

80.6 81.8

67.3 78.6

40–65 76.7 77.1

88.6 92.7

72.3 90.7

50–65 82.3 86.7

95.5 98.9

78.0 98.7

Tab. 11: Design/quality assurance input for the various constructional variants and external climates

In order to demonstrate the effects of heating the beam head the model with continuous internal insulation was used together with the most critical boundary conditions (TRY –2 kelvins, relative air humidity in internal spaces 50–65 %, with leakages). By heating the beam head with a single heating pipe at the level of the skirting board or below the beam one is not able to adequately heat the top and bottom sides of the beam. If the heating pipe is located in the masonry or two pipes are used (one above and one below the beam head) the relative air humidity and the formation of condensation can be kept stable below a critical level. It should be emphasized that the results of the investigated constructional variants depend upon such chosen boundary conditions as the material parameters, constructional details, internal and external climatic conditions as well as such simulation assumptions as the grid structure of the model. Furthermore, assumptions were made regarding the size and effect of leakages and the existing pressure relationships. The results for a certain variant can thus be the basis for an estimate of the risk of damage but they cannot replace detailed design work based on specific local conditions.

Recommendations for design, execution and communication with users in cases of internal insulation and timber beam floors Successful refurbishment with internal insulation involves the following steps: • Recording the existing situation (geometry, materials, moisture levels, use, external climate) • The analysis of variants taking into account energy consumption and the risk of failure • e xecution variants - continuous internal insulation - room-by-room internal insulation •

eam head heating with operational monitoring, for example b - with targeted input heat [Patent 2012] or - with heating pipes [Strangfeld 2012] - with heating pipes buried (s. above)

• The analysis should begin with the worst case • Internal climate in January for example 22 °C, 50 % relative air humidity • M onthly average value for external temperature in January reduced by 2 kelvins • A ssumption of leakages in systems that are executed on site involving the airtight connection of panels and/or films In general, a project for designing internal insulation should be placed in one of the following categories in order to assess the risk: Category 1: The risk of failure due to typical leakage and high moisture load due to the internal climate is tolerably small: • The monitoring (by oneself or external experts) of the execution – including leakage checks – is necessary • Short, simple and comprehensible user instructions are to be drawn up.

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Basics Category 2: The risk of failure due to minimal leakage and high moisture load due to the internal climate is tolerably small: • The necessary airtightness must be determined • A safety level must be determined • The actual airtightness must be measured on-site after construction Category 3: The risk of failure can only be kept tolerably small if there is minimal moisture load due to the internal climate: • It is necessary to analyze how the ventilation plant can guarantee negative pressure in the spaces. Here, the control of the plant (compensation of the soiling of filters) and the part load behavior are particularly important. It must be pointed out that the operation of the air conditioning plant will be necessary for the entire life of the building. Relevant questions include: - How high is the negative pressure? - Is humidification or moisture recovery planned and must these be taken into account in the design. - In such cases it is recommended that construction is monitored

Conclusions The level of knowledge about internally insulating buildings with timber beam floors built into masonry walls is still inadequate. In comparison with external insulation, the internal insulation of a building is always only the second option because of: • the intensification of the moisture problem, • the reduction of the usable space • the creation of unavoidable thermal bridges due to the connection of internal construction elements However, in a not inconsiderable number of cases including: • historically-protected buildings • adjacent plots which do not offer any legal possibility of applying external insulation (e.g. because it would be on neighboring land) • the refurbishment of individual apartments or spaces internal insulation is the only way of • sustainably reducing heat energy consumption while retaining comfort • avoiding constructional damage due to surface condensation or the growth of mold. Refurbishment to passive house or EnerPhit standards offers a range of advantages in comparison with conventional refurbishment: • Highly efficient comfort ventilation equipment (but without moisture recovery in the case of internal insulation): a needs-related rate of air change should be input in order to avoid levels of air humidity which are too low. This means that, for normal uses of spaces, relative humidities of under 40 and yet over 30 % are possible in midwinter. • Airtight building envelope, excess exhaust air: The increased airtightness of the building envelope (passive house criteria n50 ≤0.6/h or EnerPhit n50 ≤1.0/h) makes it much easier for the ventilation plant to produce negative pressure and hence prevent warm and humid ambient air from penetrating the construction. Larger plant can guarantee this with comparative ease if they are correctly regulated and the filter is regularly maintained. However, smaller plant (equipment for single apartments or rooms) is generally produced in the factory to operate with mass balancing. Manufacturers urgently need to offer some regulation. The required negative pressure is minimal as is the reduction in the level of heat supplied. • Energy efficiency: the high efficiency of all components means that the energy required for heating the timber beams using one of the methods described above is easier to justify The quality achievable in a passive house makes it possible to prevent warm humid air from continually entering critical areas such as beam heads. Reasonable levels of ambient air humidity (below 40 % in the middle of winter) due to comfort ventilation are extremely helpful in achieving this. This is shown by measurements not just in Austria but also in a number of other Central European countries. Refurbishment using passive house components thus offers optimal measures for accompanying the application of internal insulation. However, with our current level of knowledge it is not possible to offer a solid range of variants for internal insulation – nor for refurbishment using passive house elements. There is currently little more than the individual approaches set out above. But a number of research projects are currently being carried out in Germany and Austria and valid results are to be expected in the future.

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Basics It is firstly suggested that: Solutions with minimum risk of damage can only be found on the basis of dynamic hygrothermal simulations and actual boundary conditions regarding climate and use. If refurbishment projects are executed with internal insulation and, in particular, beam heads built into masonry then experienced building physicists should always be involved in the process. Systems which tolerate errors should always be preferred over riskier ones. Similarly, if required due to location and internal moisture loads, capillary conductive insulating materials with support from heating (in critical areas) should be preferred over isolating systems. Comfort ventilation without moisture recovery which operates at a slight negative pressure is a passive house solution which offers additional security.

Microorganisms on the surfaces of façades1 External thermal insulation composite systems (ETICS) are commonly used for the thermal refurbishment of external walls. Often, however, their appearance is swiftly impaired by algae and fungi which are attracted by ample levels of nutrients and humidity. The soiling of the façade as a result of both the weather and the use of the building, coupled with the organic components of the façade coating, ensure that enough nourishment is available to microorganisms. Driving rain and condensation provide the necessary humidity. Location-related factors such as the proximity of bodies of water, local climatic conditions, abundant greenery close to the building and the overshadowing of the façade can encourage the formation of surface humidity. Building physics-related factors which can also encourage such growth include the separation of the façade from the load-bearing structure and the often low storage capacity of the top surface layer – as exemplified by ETICS containing expanded polystyrene and thin layers of plaster – which can result in the surface temperature falling below the dew point with increasingly regularity and for longer periods [Breuer 2012b]. The good constructional protection of the façade from the effects of driving rain and spray and regular maintenance and repair work can reduce the risk of microbiological growth. However, [Krus 2014] conclude that the water content of the wall is less significant than the humidity of its surface. They assume that this surface humidity can be decisively reduced by “optimizing the thermal or hygric characteristics of the materials,” with special reference to the use of coatings such as phase change materials (PCM) and reflective particles (IR or low-e coatings). The state-of-the-art technological solution is to counter the formation of microorganisms by using paints and top plaster layers containing biocides [Burkhardt 2008], with encapsulated active substances playing an increasingly important role. In addition to this, coating systems using nano particles are also being developed and tested.

Chemical measures against microorganisms Biocides in façade coatings Biocides are used as film preservatives in façade coatings. In the event of surface humidity these are released from the coating material and diffused across the surface of the façade where they are absorbed by the microorganisms together with the surface water. The effectiveness of antimicrobial façade coatings is limited because in either the short or medium-term (as determined by their material characteristics) the substances are washed out of the surface coating [Burkhardt 2005]. [Burkhardt 2011] name the following substances • • • • • • • • •

1 Revised version of the chapter “The Formation of Microorganisms on the Surfaces of Façades” from: The Ecological Potential of Monolithic Building with Unfilled Thermally Insulating Honeycomb Brick, Master’s Thesis, distance learning course, Architecture and the Environment, Wismar University of Applied Sciences, Faculty of Design, Astrid Scharnhorst, September 2012

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-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) trade name Diuron 3 Isoproturon (3-(4-Isopropylphenyl)-1,1- dimethylurea) Terbutryn Cybutryn (Trade name Irgarol) O ctylisothiazolinone (OIT) D ichloroctylisothiazolinone (DCOIT) C arbendazim 3 -iodo-2-propynyl butylcarbamate (IPBC) Zinc pyrithione

The above-mentioned biocides range from being largely to almost completely insoluble in water and are consistently toxic for aquatic organisms (H400). DMCU and Isoproturon are on the EU Water Framework Directive’s list of priority materials and can probably cause cancer (carcinogenicity category 2, H351). It is assumed that Carbendazim is a source of both germ cell mutagenicity (category 1B, H340) and reproductive toxicity (category 1B, H360FD). The individual substances are also connected with other specific human or ecologically toxicological effects. [Burkhardt 2008] investigated the washing of biocides from façade coatings (plaster and two-coat paint finishes) under laboratory conditions and used the run off from façades to estimate representative occupation structures. These showed that the way in which the investigated substances, e.g. Isoproturon, Terbutryn and Dichloroctylisothiazolone (DCOIT), are washed from a surface is dependent upon temperature, the intensity of rain, the solubility of the substance in water and the built structure (façade construction and occupied surface). Under laboratory conditions it could be ascertained

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Basics that substances were initially washed out in higher concentrations and that these concentrations then fell exponentially towards zero. This suggests that waste water will probably be polluted as a result of the washing out of biocides during the first 3–5 years following the application of the coat [Burkhardt 2008a]. The effectiveness of the coating system against microbial growth also diminishes accordingly. This correlates with the statement of [Breuer 2012b], that such growth and the contamination of organic façade coatings treated with biocides could first be identified in small quantities after 3–5 years, depending upon the combination of materials. The comparable biocide-free systems already demonstrated such growth within 1–2 years. “Smart release” or “controlled release” describes a technical innovation on the market in which substances are encapsulated to enable them to resist being washed out. The antimicrobial substances are embedded in polymer beads of 10–20 μm and then released onto the surface of the façade with a delay. Both analyses under laboratory conditions by [Burkhardt 2011] and field trials by [Breuer 2012a] showed that this encapsulation greatly reduced the concentrations of biocides in the materials being washed from the façade in comparison with the direct application of the biocide to the coating. Above all, this affects the initial washing out process. In addition to this it is suspected that this will also enable the quantity of these substances to be reduced. It also appears that coatingsystems finished with color paint tend to be less susceptible to algal growth [Breuer 2012a]. The long-term environmental effect of encapsulated biocides in comparison with freely-applied substances has yet to be investigated. The assumption is that the environmental effects will be similar – but delayed. Nano particles in façade coatings The use of nano particles as an alternative to biocides is being researched and tested. This term is usually understood to refer to particles with dimensions ranging between 1–100 nm. Nano silver is used due to its toxic effect on microorganisms. [Burkhardt 2009] have studied the way in which nano silver washes out from façade coatings under both standardized test conditions and in the field. The highest concentrations of silver were found in the laboratory tests during the first phase of washing out. In the field tests 30 % of the total quantity of nano silver applied to the façade could be identified in the material washed from the façade in one year. Unlike organic biocides, which are transported to the surface due to diffusion from the coating matrix, the nano silver particles apparently become detached from the surface. In addition to this it was noted that coatings containing nano silver dried out much more slowly which also suggests an increased risk of the formation of microorganisms. There is currently very little information about the ecological toxicity, potential for bioaccumulation and biological persistence of nano silver [Burkhardt 2009]. [Fries 2009] summarized the results of various studies. According to this work there is a well-founded suspicion that, amongst other things, nano silver particles: • h ave an effect on denitrifying bacteria in wastewater and • c an pass via sludge into the agricultural chain and it is experimentally proven that nano silver particles: • h ave a toxic effect on aquatic organisms • c an permeate human skin and • c an enter cells, where they build up and can be passed onto the organism over the long term in the form of toxic silver ions. Therefore, according to [Fries 2009] and [Wefers 2009], there is a strong need for solid findings regarding the environmental and human toxicological effects of nano silver. For these reasons, the Federal Institute for the Evaluation of Risk (BfR) recommends the complete suspension of the use of nano-scale silver in consumer products until a definitive safety risk evaluation is available [BfR 2010]. The use of nano silver as an alternative to organic biocides in coatings is currently limited to a few individual products which means that its significance for the market remains marginal [Wefers 2009]. Titanium dioxide was and will continue to be primarily used as a white pigment in aggregate form. For several years it has been used in the form of nano particles (anatase, a mineral modification of titanium dioxide) as a substitute to biocides in coating systems due to its photo-catalytic properties. Under the effect of light, nano-scale titanium dioxide creates reactive oxygen radicals which can break down not only organic material on the coating but also the coating’s organic components. In the case of white pigment titanium dioxide which also contains significant quantities of nano-scale particles, [Burkhardt 2009] identified high initial levels and then ongoing continuous levels of washing out. [Kaegi 2008] revealed significant levels of nano particle titanium dioxide in the aquatic environment. This made it possible to attempt an initial estimate of the levels of nano titanium dioxide in the material being washed from surfaces. The results of this study also lead one to suspect that, in the event of heavy rain, these particles are directly discharged into bodies of water, circumventing such restraining facilities as water treatment works.

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Basics Surveys carried out to date into aquatic organisms have observed retardation in the growth of algae and the immobilization of water fleas [Hund-Rinke 2006]. [Battin 2009] observed that microbial communities became very sensitive under natural conditions – that is to say under the influence of natural UV radiation and the normal concentration of particles in surface waters. The toxicity mechanisms and the effects on the functioning and health of eco-systems should be investigated further.

Building physics measures for the avoidance of surface humidity and mineral coating systems without biocides [Künzel 2006] and [Krus 2008] analyzed the hygrothermal characteristics of paints and plasters on ETICS façades in the laboratory and in the field. They confirmed that surface water occurred in larger amounts on such hydrophobic paints as the silicon resin paint – which they investigated and which easily met the requirement for protection against driving rain – than on more permeable dispersion silicate paint or microstructure paint. In addition to this, they compared a standard thin plaster system with a thick plaster coating and coating systems with phase change materials (PCM) and IR-reflecting particles, noting that the mere use of thick plaster or of a paint with an IR-reflecting color reduced the length of time during which the temperature was below the dew point by 20 to 30 %. Even more effective results were obtained by the use of PCMs – e.g. paraffin-based PCMs – which strongly improve thermal capacity and, if the melting point is optimized in line with local climatic conditions, can reduce the length of time during which the temperature is below the dew point by 70 %. The shortest periods during which the temperature was below the dew point resulted from the combination of PCMs with an IR-effective paint. The laboratory results were largely confirmed by the field tests. It was also shown, however, that the IR coating was inadequately weather-resistant and the resulting flaking led to a clear performance reduction [Krus 2008]. The conclusion of [Künzel 2006] and [Krus 2008] is that PCMs and IR coatings offer promising reductions in the levels of condensation forming on ETICS but that these are not yet ready for implementation. [Krus 2014] used a test façade to investigate the surface humidity and drying behavior of various coating systems – on the one hand a hydrophobic silicon resin plaster system with silicon resin paint and, on the other hand, three different mineral plasters with hydrophilic façade paint. In contrast with the mineralhydrophilic coating systems the hydrophobic system demonstrated intermittently high levels of surface humidity. Hence, if the façade surface is able to temporarily absorb condensation it is not available to microorganisms as a place to grow. Hydrophilic coating systems, especially when executed as a thick coating, can thus be used to counter a certain degree of microbial growth. Among the coating systems investigated by [Breuer 2012a] were not only organic plasters and paints but also a number of variants of lime cement plaster: both without additional biocides and with five different combinations of active substances and three different paints. Levels of growth and contamination on both varieties of coating set out above (with and without biocides) only became significant (e.g. only achieved a total spread of over 5 %) after around five years. However, the biocidal effect of the total of eleven varieties of mineral coating were not evaluated in detail because these had been strongly affected by chalking and by the weather [Breuer 2012a]. Thus, an overall consideration of the biocide-free systems which had been investigated showed that the lime cement plaster was more resistant against microorganisms because the nutrients stored on the façade and, to a certain extent, the microorganisms themselves, were simply washed off together with plaster particles when it rained. It is possible that in concrete cases – and taking into account the climatic and building physics parameters – the higher maintenance and repair costs of such a purely mineral coating system can be justified by the benefits of not using biocides.

Summary of the ecological evaluation The coating systems described above can be evaluated as follows from the ecological point of view: • ( Encapsulated) biocides cannot prevent but can only delay the appearance of microorganisms on façades due to the fact that, in the short to medium term, they will be washed from the façade coatings. The adverse way in which they degrade in the environment represents an ecological and human toxicological risk. ano silver particles initially dissolve from the facade coating in large quantities as a result of which the • N duration of their effectiveness appears to be very limited. There are currently inadequate findings regarding the human and ecological toxicological effects of nano silver particles or, similarly, nano-scale titanium dioxide. oating systems with phase change materials (PCM) must be adapted to local climatic conditions and IR • C coatings have been shown to be inadequately weather resistant. The addition of organic (PCM) and metallic (IR) components to otherwise mineral coating systems complicate the recycling process. The formation of condensation and the related tendency towards the growth of microorganisms are more likely to occur on façades with hydrophobic and thin-layer coating systems. Hence – taking into account the climatic parameters and the subsequent building physics characteristics of the building – permeable, hydrophilic coating systems consisting of thick plaster which increases the thermal storage capacity of the surface of the façade and silicon-based façade paints represent a solution for external thermal insulation composite systems which is expedient in terms of ecological and human toxicology and which will also reduce surface water and counteract the growth of microorganisms on such façades. According to UBA (2014), the regular inspection and maintenance and repair of façades – such as careful wet washing or

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Basics brushing in the event of dust deposits and the first signs of organic growth – will help to reduce the risk of attack. However, these measures only apply to biocide-free façades because, otherwise, active substances could be removed.

Comfort ventilation Introduction The creation of airtight and watertight building envelopes during refurbishment projects leads to the loss of the joint-based ventilation which could provide the hygienically required rate of air changes (although joint-based ventilation alone is, in any case, unable to provide an adequate rate of air changes over the long term). The effectiveness of window-based ventilation in providing the required rate of air changes is largely dependent on user behavior as well as on the constructional situation (orientation towards or away from the prevailing wind, “wind shadows” due to trees, etc.) and seasonal variations in external temperature and humidity. Given the many requirements, window-based ventilation alone is hardly able to ensure the hygienically satisfactory ventilation of a room and generally results in loss of comfort. The recovery of sensible heat and humidity from the escaping indoor air is impossible. Furthermore, in cases of inadequate window-based ventilation and, consequently, inadequate removal of humidity, constructional damage due to factors such as mold can also occur. In contrast, the sort of well-designed and well-executed comfort ventilation commonly found in passive houses can • • • • • •

with low energy consumption and minimal noise pollution guarantee a needs-oriented rate of air changes, recover a high proportion of the heat and humidity from the extracted air, keep indoor air humidity within a comfortable range and, thereby, act preventatively against mold remove hazardous emissions resulting from building materials, furnishings and user activities filter dust and, partly, hazardous materials from the inlet air.

In addition to this, an intelligent controlling mechanism (excess exhaust air) can, for example, significantly reduce the risk of hygrothermically critical conditions in the case of internal insulation combined with the in-built heads of timber beams (see page 48). Windows can still be used for ventilation in cases of increased short-term humidity caused by, for example, cooking, showering or washing.

Options for implementing comfort ventilation The air flow volume of comfort ventilation can be either “fixed” (with a constant flow volume) or “variable” (needs-oriented). When the air flow is variable this quantity is regulated by air quality sensors such as CO2 sensors (favored in such living spaces as living rooms and bedrooms) and/or humidity sensors (favored in bathrooms and kitchens, etc.) combined with – depending upon the chosen ventilation system – either fans or regulating devices (e.g. volumetric flow controllers). If it is planned to use devices in rooms or apartments which typically make use of the indoor air, measures must be taken to ensure that these devices can either operate with circulating air (e.g. fume hoods) or without using the indoor air at all (e.g. gas boilers, primary ovens etc.). When designing service runs, fire prevention devices (e.g. maintenance-free fire shutters) must be provided whenever fire compartments (e.g. dividing walls between apartments, floor slabs) are breached. When the air flow is “fixed” it is recommended that humidity recovery (e.g. via a rotary heat exchanger) is provided for virtually every type of usage (exeption: buildings with internal thermal insulation). Due to the low humidity of the outside air, especially in winter, the inside air can otherwise be too dry. Alternatives include the building in of a humidity sensor as a means of being able to vary air flow or the provision of appropriate user training. In designing and laying out ventilation ducts – especially in the case of centralized ventilation systems – it is important to consider that these ducts will enable noise to travel between different rooms and apartments. For this reason, appropriate sound insulation devices such as mufflers must be provided. In addition to this, the design of the ventilation ducts and of any in-built components should seek to minimize resistance – and, hence, pressure loss – in order, in turn, to minimize the energy required to move the air. For example, the passive house criteria of 0.45 W/m³h for the entire ventilation system (inlet and outlet air fan, including control system and auxiliary drives) can be met by a volumetric flow controller without primary pressure, low velocity air diffusers etc.

The dimensioning of – and a discussion of – volumetric flows Recommendations of air volume There are various recommendations for dimensioning the air volumes of residential ventilation systems with heat recovery ([ÖNORM H 6038:2014] [EN 15251], [DIN 1946-6:2009], [SIA 382/1], Passivhausinstitut, www. komfortlüftung.at etc.). The dimensions recommended by the various norms are similar and tend to differ only in detail, partly because the norms have very different focuses. For the dimensioning of passive

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Basics houses, an inlet air volume of 30m³/h per adult is used as a basis whereas 60, 40, 20 and 20 m³/h are demanded for the outlet air volume for kitchens, bathrooms with WCs, bathrooms without WCs and WCs respectively. In the case of office buildings, the air volume levels required by the passive house guidelines are significantly below the levels defined by EN ISO 13799 on the basis of indoor air quality and the assumed levels of hazardous material emissions from building materials. If the project is well-planned and if the emission of hazardous materials is minimized by quality-assured product management and the replacement of problematic old building materials, a high quality of indoor air is also guaranteed by a volume of 30m³/h per person. High air volumes generally increase the need for air conditioning (principally, for humidifying and dehumidifying the inlet air) and increase the amount of electricity consumed in delivering this air. For schools and kindergartens, passive house design recommends a volume of 15 to 20m³/h per person. In addition to this, and just as in the case of passive house design, all the norms mentioned above categorically demand the provision of a needs-oriented ventilation system which adjusts the air flow volume in line with presence/absence and other requirements. In the case of pure (= monovalent) air heating the air volume recommendations of the Passivhausinstitut are to be followed without exception. As the heating function means that the air volume cannot be reduced in cases of absence, the higher rates of air changes will lead to dry air. In colder climates it is basically recommended that monovalent inlet air heating should be avoided. When the equipment is installed it must be adjusted in line with the defined air volume. In the event of passive house certification, measurements must be taken in every room to confirm that these volumes have been achieved. Optimization of air volumes – cascade utilization

Corridor

When ventilating living spaces the air is utilized as a cascade in order to ensure the needs-oriented adjustment of the total air volume: The inlet air is injected into the spaces requiring inlet air (bedrooms, living rooms) and then fed into overflow areas (corridors) before finally being extracted from outlet air areas (kitchens, bathrooms, WCs). By integrating the living room into the cascade as the overflow area from the bedroom the air volume can be optimized further (extended cascade). For a more detailed presentation see [Pfluger 2013].

Kitchen, Bathroom WC

Fig. 87: Cascade-form of airflow with and without the integration of the living room

By integrating the living room into the cascade in this way the inlet air volume into the bedroom can be reduced accordingly. Under normal usage patterns the combination of a parents’ bedroom and living room will extend the use period. On the other hand, the combination of children’s bedrooms and living rooms rarely results in a reduction of air volume because both areas are often occupied simultaneously. Optimization of air volumes – adjustment in line with demand The adjustment of air volumes in line with demand (presence level, absence level, intense level) and extended cascade utilization are the most important ways of optimizing air volumes. Air volumes can be ad-justed in line with the conditions “absent” and “present” either manually or automatically. The intense level (cooking or party) is always triggered manually. Automated systems control air volumes in line with time programs, air humidity, CO2 content or mixed gas concentrations. In the case of time programs it is important that a seven-day program is used that can react to the different daily routines at the weekend. Air volumes should, in particular, be adapted to the “present” and “absent” conditions when the external temperature falls below 0 °C. The limitation of the air volume prevents air humidity from falling too strongly. For reasons of efficiency (electricity demand, heat loss) an adjustment should be made for an entire year.

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Basics Decentralized and centralized systems The basic options for ventilation are centralized, decentralized (per room, per apartment) and semi-centralized (e.g. per staircase) systems. The following remarks refer to apartments in multi-family houses but similar principles apply to office and school buildings. Single room ventilation unit, several units per apartment In refurbishment projects it is usually too complicated to add a single centralized unit for an entire building or apartment. Hence, room-based solutions are implemented. In these, a ventilation unit is installed in each room. Outside air is injected, filtered and warmed separately in each room. Ideally, the units are mounted on the external wall. Air ducts are only required in the case of internally located rooms. When ducts pass through external walls care must be taken to ensure that the openings are airtight. Whether thermal bridges occur depends strongly upon the characteristics of the materials. It is important to note that the outlet air duct also carries condensation. In unfavorable situations icicles can form in winter and ice can collect on the pavement! Appropriate precautions must be taken. The controls in each room – which can use air quality sensors or be manual - are fully independent. Access to the affected rooms must be guaranteed for reasons of maintenance and repair. A disadvantage of the single room solution is that no use can be made of simultaneity (as exemplified by cascade ventilation). In addition to this, noise is generated inside each room as a result of which only “quiet” units should be used. Typical noise levels for single room ventilation units are set out, for example, in [Gruber 2015]. An advantage of this approach is that constructional interventions are only required in the external wall and can be carried out at little extra cost – at the same time, for example, as the replacement of the windows. If a decentralized ventilation unit is to function optimally it must be positioned in such a way that it is unaffected by furniture, curtains or other objects. Furniture or curtains can impede air flow. Similarly, drafts can affect people seated too close to the unit. In technical terms there is a difference between ‘continuously operating’ and ‘reverse cycle’ ventilation units. Continuously operating units work like a ventilation unit for an entire apartment or building but are simply correspondingly “reduced” in size. An inlet air fan draws outdoor air across a filter and heat exchanger into the apartment while a second fan draws the outlet air back across the heat exchanger and to the outside. If, for constructional reasons, the distance between the two fans is too small there can be a form of short circuit between the inlet and outlet air. This short circuit must be reduced as much as possible and, in all events, the limiting value for passive house certification must be respected. Reverse cycle units, which are also often referred to as pendulum ventilators, contain heat exchangers through which inlet and outlet air is alternatively drawn in cycles which, depending upon the manufacturer, vary between 50 and 75 seconds. This alternating passage of cold and warm air results in the transfer of the energy stored in the heat exchanger block to the inlet air. Wherever possible, reverse-cycle units should be installed in apartments in pairs, with one unit extracting air from the apartment while the other injects it into the apartment (in order to avoid positive and negative pressure). To this end, the units should be coupled together. In general, continuously operating and reverse cycle systems work equally well. The major differences involve filtering quality, which is consistently lower in the case of reverse cycle units. Ventilation units which ventilate two rooms at the same time have the advantage that a single unit can create a cascade formed from an inlet air room and an outlet air room – as, for example, when a bedroom & bathroom, living room & kitchen or children’s bedroom & WC are combined. The units should be installed in rooms where noise is less critical (kitchens, bathrooms, WC). The cascade effect reduces the total air volume due to the fact that the fresh air is first used for the ventilation of the inlet air room (e.g. bedroom) and only then for dehumidifying and extracting air from the outlet air room (e.g. bathroom). With two or three units, each of which serves two rooms, a satisfactory solution can usually be found for an entire apartment. Decentralized ventilation units, one ventilation unit with heat recovery per apartment Each apartment has its own ventilation unit which is installed in a plant room or area. If rooms are high enough, in-built ceiling-mounted units can also be used. It is possible to inject the outside air directly into each apartment but a central outside air duct is the better solution. This outside air is then filtered and heated individually for each apartment. It is also better to extract the outlet air from the building via a central outlet air duct. The air is distributed within the apartment via, for example, the ceiling to the vestibule (corridor) which contains ceiling mounted ducts for the inlet air and overflow openings for the outlet air. The ventilation in each apartment can be separately controlled quite independently from other ventilation units/apartments. Good design and high quality equipment can improve noise protection with relative ease. It must be possible to access the affected apartments for reasons of maintenance and repair. Simultaneity effects cannot be exploited due to the different use profiles of the different apartments.

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Basics Centralized or semi-centralized unit A single central ventilation unit is planned for one or several objects. The injected outside air is centrally filtered, heated and possibly, in summer, cooled for each object. The unit can be installed in, for example, a basement or a roofspace or on a flat roof and, ideally, within the thermal building envelope because, otherwise, a special weatherproof unit must be used. Ducts are to be kept as short as possible. These ducts should pass between stories in existing or newly created vertical shafts and distributed within each story above the corridors – if there is enough free height. Each apartment must have appropriate volumetric flow controllers to regulate air volumes. These can be controlled manually or by air quality sensors. Alternatively, decentralized mini fans can also be used. The centralized injection of the inlet air and extraction of the outlet air ensures that the heat exchanger transfers the heat energy from the outlet air to the newly injected inlet air. Repair and maintenance needs are met by guaranteeing access to the plant room. High quality noise protection can be guaranteed by appropriately installed mufflers.

Selection criteria Alongside technical and financial criteria, the decision in favor of a certain system should be informed by other boundary conditions: • • • •

Who are the apartment users? How much should/must/can they decide/be responsible for themselves? Does the existing building have space for ventilation ducts? For both vertical and horizontal distribution? Does the comfort ventilation have to be installed while the building continues operating? What is the level of external noise pollution?

Dependent upon the intended apartment standard (Investment costs) there are several possible forms of ventilation system: Ventilation system

Tab. 12: Suitability of different ventilation systems for different apartment standards + highly suitable o neutral – less suitable

Standard Comfort apartments apartments

Centralized ventilation plant, constant volumetric flow

o –

Centralized ventilation plant, variable volumetric flow

+ o

Decentralized ventilation units, 1 ventilation unit with heat recovery/apartment

o +

Single room ventilation units, Several units per apartment

o –

Each ventilation system has constructional implications which should not be overlooked – particularly concerning the size of ventilation shafts. A requirement to work with existing structured façades also has consequences for the choice of the ventilation system.

Tab. 13: Building-related issues raised by different ventilation systems

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Ventilation system Ventilation shaft (cross-section over 1 m²)

Ventilation plant room (possibly together with other technical plant )

Original façade (stucco, structured)

Centralized ventilation plant

Necessary

Unproblematic

Necessary

Decentralized ventilation units, Partly necessary Partly necessary 1 ventilation unit with heat recovery/apartement Single room ventilation units, Not necessary for Not necessary for several units per apartment ventilation ventilation

Problematic where the injec- tion of inlet air or extraction of outlet air is also decentralized Problematic (airtightness of building envelope, removal of condensation…)

Details of Passive Houses: Renovation

Basics Basically, passive house certified ventilation units capable of meeting high energy requirements are available for all typologies of comfort ventilation (see www.passiv.de). Decentralized per room Decentralized per apartment

Centralized per building (semi-centralized per staircase

Technical Data Effectiveness

Above 90 %

Approx. 90 %

Approx. 90 %

Volumetric flow 30 to 50 m³/h Approx. 100–150 m³/h

Dependent upon number of apartments per staircase per building, e.g. MENERGA 5,000–2,000m³/h

Typical dimensions (B×H×D mm)

Dependent upon air volume -> number of apartments/ ventilation units: e.g. MENERGA 5000 m 3/h approx. 4,180×1,050×1,410 cm (L×B×H)

Window sill unit: approx. 1 130×105×220 HELIOS wall unit: approx. 598×730×320 SIMKA wall unit: approx. 515×700×210 Drexel&Weiss wall unit: approx. 600x745x600 HELIOS wall unit: approx. 370×396×350

Minimum wall thickness approx. 20 cm Consider stability of wall in event of wall fixing Diameter • borehole • casing • ventilation duct

Borehole: diameter approx. 35 cm Window sill unit: approx. 110×10 cm

Electricity requirements

approx. 8–16 watts

approx. 80–160 watts

Generally, ventilation units are not structurally relevant, except special solutions

e.g. MENERGA 5,000 m 3/h 3,8 kW

Noise Noise level, sound insulation (limiting value for living spaces LAF max ≤25 dB)

e.g.: HELIOS, Emission L PA in 3 m e.g.: HELIOS, ZUL: L WA 52–64 dB(A) 18–30 dB(A), for best units at ABL: L WA 36–48 dB(A) lowest levels below 20 dB Emission L PA in 1 m 41–50 dB(A) [Gruber et. al 2015]

Dependent upon execution of unit, free choice of mufflers e.g. MENERGA 5,000 m 3/h without mufflers 77–88 dB(A); further mufflers from other manufacturers (e.g. TROGES, TROX …)

Internal comfort, injection of inlet air

To external face of wall, partially free Air injected via ventilation openings, choice (together with position of unit), individually positionable for optimal comfort largely determined by con- conditions, independent of unit structional characteristics

Air injected via ventilation openings, individually positionable for optimal conditions, independent of unit

Constructional aspects Connection with the airtight Critical for the airtightness of the object level due to the number of penetrations Thermal bridge effects

Significantly more due to number of pene- trations, good execution methods available

In case of combined inlet and outlet air openings just 1 per common opening, in case of individual inlet and outlet openings critical due to number

Only at the point of penetration, 1 each for injection of inlet air and extraction of outlet air

In case of common inlet and outlet air openings Only 2 duct openings relatively unproblematic

Possible excess of extract air Not possible Not possible with most products (see chapter internal insulation)

Possible in principle

Protection against driving rain

Dependent upon position, more flexible than single room ventilation

One central inlet and outlet to be built by main contractor, (partly prefabricated components)

Each apartment individually, each room only with volumetric flow controller, limited use of simultaneity

Each apartment individually dependent upon number and position of volumetric flow controllers -> Possible use of simultaneity across entire object!

Construction 1 wall opening per room, electrical con- nection, control (remote?)

Fixing of ventilation unit, possible shaft in case of joint inlet/outlet air, ducting inside apartment

Shafts needed across several stories -> space requirement! Only volumetric flow controllers and mufflers in apartments, filters optional

Operation / maintenance / To be organized by apartment user, to be repair present and every room to be accessible

To be organized by apartment user, access to room with ventilation unit, limited access to other spaces (ventilation openings)

To be organized by building owner (or representative, access to plant room necessary, limited access to apartments and rooms (volumetric flow controllers)

Main materials (typically) Casing

Galvanized steel sheet

Galvanized steel sheet

Plastic if laid within floor construction (space requirements!) otherwise galvanized steel sheet

Vertical shafts: galvanized steel sheet, within apartments: plastic if laid within floor construction (space requirements!) otherwise galvanized steel sheet

Dependent upon model, manufacturer and position

Controllability Room-by-room (range dependent upon unit) Work required within apartment

Plastic

Ducts/conduits Not necessary

Elements within ducting Not necessary Plastic / galvanized steel sheet

Principally galvanized steel sheet, small amounts of plastic

Available filter qualities

Free choice

G3–G4, F5–F7

F7, G4



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Basics Decentralized per room Decentralized per apartment

Centralized per building (semi-centralized per staircase)

Maintenance By whom? By apartment user

By user (central elements of plant in agreement with building owner (or representative)

Accessibility Each room in agreement with user To “plant room” and central elements of plant

By building owner (or representative) To central elements of plant or also to apartments in the case of decentralized elements of plant (volumetric flow controllers…)

Repairs By whom? By apartment user

By user (central elements of plant in agreement with building owner (or representative)

By building owner (or representative)

Accessibility Each room in agreement with user To “plant room” and central elements of plant

To central elements of plant or also to apartments in the case of decentralized elements of plant (volumetric flow controllers…)

Replaceability Only by same unit or successor unit

Within the “system” (different for each manufacturer generally unproblematic, in case of changing manufacturer, adaptations are generally necessary

The space available and space requirements usually determine the potential for replacing the unit with another product.

Tab. 14: Comfort ventilation systems

Conclusion The execution of comfort ventilation as part of a building refurbishment project poses a series of special challenges. Special attention should be paid to those qualities which affect the acceptance of the equipment by the users such as low noise levels in the rooms, low levels of drafts and ease of cleaning. However, if well-designed and well-executed, comfort ventilation represents an energy-efficient and comfortable way of combining the needs-related rate of air changes with high constructional reliability.

Harmful substances in existing buildings When handling legally regulated materials one is obliged to, firstly, avoid all risks regarding any future use of a building and, secondly, correctly dispose of all dangerous materials and other waste generated by the demolition of a building in line with the relevant legislation. Here it is important to identify dangerous waste and to avoid mixing this with other waste. In addition to this, an orderly demolition makes it easier to achieve the highest possible degree of recycling. In the case of unregulated harmful materials, the objective of the removal of such dangerous materials must be the long-term protection of building users in line with the precautionary principle. If there is the slightest risk of contamination due to harmful substances during a building refurbishment project, experts must be brought in. Without making any claim to be exhaustive, this chapter offers an initial overview of: 1. Harmful substances for which there is already a legal basis for the protection of building users. These also include harmful substances which are the subject of use or manufacturing bans. 2. Harmful substances which are not the subject of use or manufacturing bans and for which there is either no or little legal basis for protecting building users and workers. 3. Biogenic harmful substances such as molds and timber-destroying fungi but excluding bacteria. 4. Harmful substances which can be introduced via new building products and which can considerably affect internal ambient air quality. Further information can be found in the guidelines, norms and specialist literature listed below.

Contamination of existing buildings Harmful substances such as those set out in Table 14 were widely used in buildings during the era up until the 1980s which is under consideration here. The human and eco-toxicological characteristics of these substances led to them being classified as carcinogenic, mutagenic, reproductive-toxicological and/or persistent organic pollutants (POP). For this reason – and in order to protect both building users and those who work every day with these substances – not only is the evaluation of the danger and the determination of the urgency of refurbishment of such buildings legally regulated but there is also a precautionary requirement to minimize concentrations in internal ambient air. Legally regulated harmful substances in the EU include: • Asbestos fibers • Thermal insulation made from artificial mineral fibers (AMF) which, here, refers exclusively to AMF of previous generations manufactured before 1996 or 2000 • Dichlorodiphenyltrichloroethane (DDT) or hexachlorocyclohexane (lindane), which were used for the preventative chemical protection of timber building elements

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Basics • Pentachlorophenol (PCP), which was principally used as a means of protecting wood • Polychlorinated biphenyls (PCB), which are largely used in building products such as softeners or flame retardants • Polycyclic aromatic hydrocarbons (PAH) which are typically found in products containing tar and also in combustion products or residues The overview shows typical areas of use, periods of use and modes of use of these substances

Harmful substance Asbestos fibers Area of use Lightly-bound asbestos products (density 1,000 kg/m³, asbestos content up to 15 %) - Asbestos cement panels as roof or façade sidings, window sills - Asbestos cement pipes/molded objects, e.g. flower pots, duct sidings, coverings - Asbestos/PVC products as flooring materials

Thermal insulation made from artificial mineral fibers of the older generation (AMF) - Matting, panels or molded objects - Thermal, impact sound and acoustic insulation in wall, roof and ceiling areas - Sprayed fire protection insulation, easily bound with cement AMF - Thermal insulation material in the field of building services (pipe work, electric storage stoves)

Building element

- External walls - Separating and connecting joints - Internal walls and ceilings - Floor slabs - Beams and columns - Roof - Windows/doors - Pipes/wiring/ducts - Equipment/Installations (heating equipment, lift)

- External walls - Separating and connecting joints - Internal walls and ceilings - Floor slabs - Beams and columns - Roof - Windows/doors - Pipes/wiring/ducts - Equipment/Installations

Period of use and regulations

- Large-scale introduction of asbestos fibers with asbestos cement around1900 - Highpoint of production in the mid-1970s - Banned in Germany since 1993 (GefStoffV) - Banned in Austria since 1990 ([BGBl 324/1990], [BGBl 477/2003]) - Banned across the EU since 1.1.2005 (2003/18/EG)

- - - - -

Production until around1996 Change of recipe and phased switch from old to new generation AMF between 1996 and 2000 Manufacture and use banned in Germany since 1.6.2000 (GefStoffV). Exception: as part of restoration work, reinstallation of previously dismounted materials, dependent upon fiber content Demolition, refurbishment and maintenance work on old AMF in Germany only in line with [TRGS 521] If no information is available about the age and/or fiber characteris- tics of AMF in existing buildings it should be treated as old generation AMF as a precaution

Health

- - - - - - -

- - -

Carcinogenicity K2 (CLP-VO), valid for respirable, bio-persistent AMF fibers (length >5 μm, diameter 3:1). Exceptions: Notes Q and R in line with (CLP-VO) Carcinogenicity K2, K3 or release in line with (TRGS 905) dependent upon carcinogenicity index Skin irritation

Means of transmission

- Air/respiratory tracts

Lightly-bound asbestos products are particularly relevant in terms of their health effects Carcinogenicity K1a (CLP-VO) Long-term chronic toxicity High latency period 10–60 years (fibers have a very high resistance inside the lung) Asbestosis/pulmonary fibrosis Lung and throat cancer Mesothelium (tumors of the pericardium, pleura and peritoneum)

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Basics Harmful substance

Lindane (γ-Hexachlorocyclohexane (HCH))

DDT (Dichlorodiphenyltrichloroethane)

Area of use

- Wood protection agent (preventative chemical timber protection applied by painting) - Insecticide/plant protection agent

- Wood protection agent (preventative chemical timber protection applied by painting) - Insecticide/plant protection agent

Building element

- Timber building elements/timber stud wall construction in external and internal walls, in roofs and ceilings, in areas in contact with ground - Façade sidings, wooden doors and windows and other areas exposed to the weather - Panels or sidings of internal walls and ceilings - Secondary contamination of all surfaces adjacent to treated element in form of residues from pest control measures or in dust

- - -

Timber building elements/timber stud wall construction in roofs, rooftop apartments often affected Treatment of in-built timber elements or furniture Long-term contamination of internal ambient air and possible residue in dust

Period of use and regulations

- - -

- - - - -

Industrial production since 1939 Banned in the BRD since 1972 (DDT-Gesetz, now ChemVerbotsV), Use of remaining DDR supplies until1991 Banned in Austria1993 (BGBl 652/1993) Since 2004 global action plan with aim of reducing production and use of DDT (exception: production and use for fighting causes of disease) and eventual discontinuation (Stockholm Convention) Banned persistent organic pollutant (850/2004)

Health

- Acutely toxic when swallowed, breathed in or in contact with skin - In cases of lengthy or repeated exposure lindane can damage organs and have further effects on blood production, immune system, liver - Can damage babies via mother’s milk - Carcinogenic K3 (TRGS 905) - Concentration in organisms due to high fat solubility (high persis tence)

- Danger through breathing in of crystals and dust particles - Carcinogenicity K2 (CLP-VO) - Acutely toxic when swallowed (CLP-VO) - Persistent organic pollutant, POP (Stockholm Convention) - Lengthy or repeated exposure can damage the organs (CLP-VO) - Suspicion of hormonal effect - Concentration in organisms due to high fat solubility (high persis tence)

- Air/respiratory tracts - Skin

- Air/respiratory tracts - Food/digestive tract

Means of transmission

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Technical HCH banned in BRD in 1977, EU-wide 1981, only remaining use of 99 % γ-HCH as insecticide in wood protection agent since 1983 Use of wood protection agent containing lindane not banned in Germany, but no approved product remains on the market and largely replaced by pyrethroid Banned persistent organic pollutant (850/2004)

Harmful substance

Polycyclic aromatic carbohydrates (PAH)

Area of use

- Seals in buildings: roofing membranes/roofing papers, paintwork in contact with ground - Insulating material: tar-bonded cork insulation panels - Floor coverings: adhesives for parquet and woodblock paving, mastic asphalt and screeds - Impregnation: wood protection agent for fire-resistant building materials - Joint sealer

Building element

- Floorplate - Walls in contact with ground - External cavity wall - Separation and movement joints - Floor slabs and floor construction - Internal walls and ceilings - Roof - Chimneys - Windows/doors

Period of use and regulations

- Parquet adhesives containing tar between around 1900 and the late 1970s - Woodblock paving adhesives containing tar until 1999 - From 1970 switch to bitumen

Health

- - - -

Means of transmission

- Food - Drinking water - Air/respiratory tract - Skin

Many connections are carcinogenic, mutagenic, toxic to the immune system and the liver Irritative effect via mucous membranes, allergic skin reaction Effect on blood production, kidney and liver damage, heart failure at high exposure levels For the primary substance Benzo[a]pyren: Carcinogenicity 1B, germ cell mutagenicity 1B, reproductive toxicity 1B (CLP-VO)

Details of Passive Houses: Renovation

Basics Harmful substance

Pentachlorophenol (PCP)

Polychlorinated biphenyls (PCB)

Area of use

- - - - - - -

- Permanent elastic sealants - Color and fire protective paints - Colored plaster - Floor covering adhesives - Grouts and fillers - Cable sheathing - Capacitors/transformers - Hydraulic plant and electric storage stoves - Secondary contamination of untreated building elements via internal ambient air

Building element

- External walls - Internal walls and ceilings - Floor slabs and floor construction - Roof

- Separation, movement and building joints - Internal walls and ceilings - Floor slabs and floor construction - Windows/doors - Pipes/wiring - Equipment/installations

Period of use and regulations

- - - - -

Industrial production since 1945 Mandatory labeling since 1978 Manufacture, marketing and use of products containing more than 5 mg/kg PCP banned in Germany since 1989 (ChemVerbotsV) Manufacture, marketing and use of products containing more than 0.01 weight % PCP banned in Austria since 1991 (BGBl. Nr. 58/1991) According to (REACH-VO) there is an EU–wide ban of the marketing of products containing more than 0.01 weight % in materials or products

- Manufacture/use since 1929 - 1973 recommendation of OECD to limit use of PCBs to closed systems (e.g. capacitors); 1978 implementation of recommendation into Ger man law - Use of PCB jointing material between 1955 and 1975 and partly to 1990 - Use in elastic sealants until around 1972 - Use in plasters until around 1973 - Use in capacitors/transformers until around 1984 - No production in Germany since 1983 - Manufacture, marketing and use of products banned in Austria since 1993 (BGBl 210/1993) - EU guidelines (96/59/EG) on the elimination of PCB etc. including objective of complete decontamination and elimination - Global timetable and action plan (Stockholm Convention): removal of PCB from all equipment by 2025, disposal of all PCB (applies to products >50 ppm PCB) by 2028

Health

- - - - - - -

POP Irritation of eyes, skin and respiratory tract Acute toxicity upon breathing in, skin contact or swallowing Carcinogenicity K2 (CLP-VO) Reproductive toxicity Re2 (TRGS 905) Mutagenic M3 (TRGS 905) Toxic pollution with polychlorinated dioxins and furans due to manu- facturing process

- - - - - -

Means of transmission

- Food - Air (gaseous or particulate)/ respiratory tract - Skin

Preventative protection of timber building elements, e.g. façade sidings, roof structure, stairs and balustrades, windows and external doors and timber sidings Measures against infestation from insects and preventative measures against fungi in roof construction Removal of dry rot from masonry and plaster Preservative in paints, adhesives, textiles and cellulose Use as plant protection and disinfection agent in sanitation, forestry and cosmetics Extensively used with γ-HCH (lindane) Secondary contamination of untreated building elements via internal ambient air

POP Lengthy or repeated exposure can damage the organs (CLP-VO) Carcinogenicity K3 (TRGS 905) Reproductive toxicity Re2 (TRGS 905) Impairment of ability to reproduce Rf2 (TRGS 905) Toxic pollution with polychlorinated dioxins and furans due to manufacturing process

- Food - Skin - Air (gaseous or particulate)/ respiratory tract

Further reasons for precautionary refurbishment measures could include building elements or paints which contain heavy metals such as lead or use or maintenance-related contamination (e.g. pesticides resulting from disinfection measures or mercury left behind by mirror production etc. (see. LfU 2003)). Whether such precautionary measures are necessary can be indicated by toxicologically-based reference values which are generally recognized by statutory authorities or professional bodies but not laid down by law. These reference values assume continuous, full-day use of the spaces and take high-risk groups into account. If the spaces do not exceed these precautionary values it can be assumed that even long-term exposure will not lead to adverse health effects (Ad-hoc-AG IRK/ALOG 2007).

Tab.14: Overview of typical primary and secondary harmful substances in existing buildings. Sources: [ÖN S 5730], [Zwiener 2006], [Berg 2010] and the regulations and guidelines named in the table 

The investigation of harmful substances in existing buildings If there are grounds for suspecting the presence of harmful substances in an existing building, harmful substance specialists and other experts must establish – in line with the valid regulations and guidelines – whether and which harmful substances are present and which decontamination or disposal measures are required in order to remove all danger and take all necessary precautions. Different European countries address the investigation and removal of harmful substances in different ways. In Austria, the Recycling and Building Materials Regulations [BGBl. II 181/2015] require that qualified persons carry out a Harmful and Impure Materials Investigation in line with ONR 192130 or ÖNORM EN ISO 16000-32 for all building projects with a total internal volume of over 3,500 m³ or which produce more than 100 tons of building and demolition waste, excluding excavated ground. This investigation is to include:

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Basics • • • •

research into the location, construction and use situation a site visit the planning and carrying out of the taking of samples and analysis of these samples the evaluation of the results of this harmful substances investigation and, if necessary, recommendations for decontamination measures • the documentation of this harmful substances investigation

For building projects with smaller gross volumes the Recycling and Building Materials Regulations require the carrying out of a Preliminary Harmful Materials Investigation in line with ÖNORM B 3151. In case no such or similar regulations exist at national level the above mentioned norms – or other guidelines, tools (e.g. [LfU 2003]) or online information systems (e.g. the harmful material guidebook for the demolition of buildings) – can provide an initial orientation and be used for the evaluation of an existing building. The documentation of the harmful substances investigation forms the basis for harmful substances-related decontamination measures. The polluted building elements must be removed, physically separated, coated, clad or chemically treated/coated in line with the agreed decontamination measures and the legal and norm-related requirements. It is possible that only the affected areas or individual surfaces must be removed from building elements. Secondarily affected materials or objects such as furniture or textiles are to be removed or cleaned in line with the decontamination requirements. After the completion of this decontamination work there must be no residual health risk for users [Zwiener 2006]. The success of the decontamination should be demonstrated by, for example, measurement of the internal ambient air. Ideally – and in line with the precautionary principle – the target values set out in Table 18 should be achieved. The contaminated building and demolition material should be treated and disposed of in line with the relevant national waste removal regulations.

Biological threats Biological threats due to molds Molds relevant to internal spaces Of the more than 100,000 recognized species of mold, 200 occur in connection with humidity damage and just 50 do so regularly. Only a few such species are characteristic for humid building materials or fabric [Zwiener 2012].

Type Stachybotrys chartarum, Accremonium spp. Phialophora spp., Engyodontium album Aspergillus penicillioides, Aspergillus restrictus, Eurotium spp., Wallemia sebi Aspergillus versicolor, Chaetomium spp., Trichoderma spp. Tab. 15: Typical species of mold for humid building materials or fabric. Table after [Zwiener 2012], p. 488)

Typical source Building materials containing cellulose, very humid Humid plaster Building materials containing cellulose, slightly raised humidity Humid building fabric

Causes of mold infestation in internal spaces Mold is caused in internal spaces by increased levels of humidity. These can be caused by • hygrothermic factors, meaning that they result from inadequate ventilation and/or heating, deficient air circulation or building defects such as thermal bridges • damage to the building, meaning that building elements are very humid due to, for example, rising damp, roof leaks or such incidents as broken pipes • and/or additional moisture generated by, for example, laundry or plants In addition to the increased humidity of internal spaces, other factors affecting the growth and spread of mold include ambient air and surface temperatures, the availability of nutrients, pH values, surface finishes and the incidence of fungi and molds in the vicinity. If building elements becoming humid and growing conditions are good, mold begins to grow within 3–7 days of the incident. Hence, the time factor plays a decisive role in the elimination and avoidance of damage [UBA, 2005]. Effects of mold on health The health-threatening effects of molds result from their fibrous cells (hyphae/mycelia), their propagation units (spores/conidia), the metabolic products in and on these spores and mycelia (mycotoxins) and microbiologically produced volatile organic compounds (MVOC). The latter are discernible as a typical moldy odor and often act as an indicator for invisible mold infestation. The above mentioned constituent parts of molds and their emissions can lead to the following problems for weaker groups of people such as those with allergies, low immunity or chronic respiratory illnesses: • allergization and allergic reactions such as asthma, rhinitis and allergic alveolitis • respiratory, eye and skin irritations such as MMIS (Mucous Membrane Irritation Syndrome), ODTS (Organic Dust Toxic Syndrome)

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Basics • infections such as pulmonary mycosis • intoxications (mycotoxins) with carcinogenic, neurotoxic, mutagenic, immune-suppressive, organdamaging and other effects Typical symptoms include the above-mentioned irritations or allergic reactions, flu symptoms, fatigue symptoms (chronic fatigue syndrome), loss of concentration, digestive disorders and nausea [Zwiener 2012]. Course of action in cases of (suspected) mold infestation If there is a suspicion of mold infestation due to, for example • • • •

visible damage the humidity of materials or building physics abnormalities without visible damage health problems, or the characteristic unpleasant odor of mold

the first action should be the drawing up of a detailed case history of the building. This can, for example be drawn up on the basis of the “Mold Guidelines” (UBA, 2002) or “Mold Decontamination Guidelines” (UBA, 2005). This involves a visit to the building and an investigation of the basic conditions. If visible mold infestation can be found this should evaluated – backed up in certain situations with material and surface contact samples - and a decontamination concept drawn up. If no mold infestation is visible and, hence, there is merely the suspicion of mold infestation a measurement strategy is to be drawn up taking into account the circumstances of the site visit – which could include material humidity, health problems or odor problems. The following methods can produce suitable proof: • Material samples in cases of humid materials or during the control of refurbishment work or in cases of suspicion of disinfection2 • Air samples – plus additional material samples – in order to measure the concentration and type of mold and also in connection with references to possible sources • Dust samples in cases of suspicion of secondary contamination • Sniffer dogs in cases of hidden infestation and suspicion of MVOC This approach also concludes with an evaluation and the drawing up of a decontamination concept. If extensive decontamination measures – which must always be carried out by experts – are required the urgency of this work and the threat to users and employees must first be established. This evaluation should take into account the national regulations for the protection of employees against biological materials (see for example [VbA 1998], [BioStoffV 2013] and [BGI 858]). The necessary protective measures and decontamination work will be carried out accordingly. It should be noted that a single disinfection is often not enough because exterminated mold can still give out health-threatening mycotoxins. The work should always end with fine cleaning and a control of the decontamination measures. The objective of the decontamination of mold-infested internal spaces is to reestablish the usability of the room or building. Biological threats due to wood-destroying fungi Wood-destroying fungi present a further biologically-related danger. However, the focus here is on the retention of the building fabric because the infestation of wood and wood materials can also affect the structural elements within a building with the result that the safety of users is no longer guaranteed. Health concerns play a secondary role here although some species of wood-destroying fungi have the same irritative or sensitizing effect as molds. In order to grow and spread, wood-destroying fungi primarily require high levels of humidity and this, in turn, increases the danger that infestations of other molds – and their corresponding health effects – will also arise. Fungi which, rather than destroying wood, merely infest it without weakening or destroying the building fabric are not considered here. On the other hand, however, such fungi can naturally offer an indication of increased humidity and, thus, an invisible infestation of wood-destroying fungi [Berg 2010]. Causes, sources and the spread of wood-destroying fungi In order to grow and spread, wood-destroying fungi require increased levels of material humidity which, depending on the species of fungi, must be considerably higher than the fiber saturation level of the wood which, while different for every species of wood, has an average of 30 %. One exception to this is dry-rot which can also occur despite lower levels of humidity in the wood. Possible causes for increased levels of humidity in materials include: • large-scale damage to the building such as the heavy soaking of building elements due to a broken pipe, flooded basement or similar event • leaks in walls, roofs or building elements in contact with the ground • building physics-related increased humidity resulting from, for example, thermal bridges and the resulting condensation • inadequate drying-out times during new building or refurbishment work [Zwiener 2012]

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2 Suspicion of disinfection: A case in which it is suspected that disinfection materials were used during an earlier decontamination but that the affected material was inadequately or incorrectly removed.

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Basics As in the case of molds, the building element is infested by spores which are carried in the air. In favorable growth conditions these develop into mycelia and, later, fruiting bodies. In addition to this, wood-destroying fungi can also be introduced in building material which comes from humid parts of a building or through the use or re-use of such materials as recycled timber or bricks from demolished buildings. In addition to this, there is also a danger that spores can be spread by building users. Wood-destroying fungi infest building elements and objects made of wood or wood products such as structural timber elements in roofs and walls, doors, flooring materials and wall panels as well as other cellulose-based materials such as books and wallpapers, etc.. Some species also grow on porous or cracked masonry. Wood-destroying fungi dissolve the necromass from both without and within. The destruction of the wood is often well advanced before the infestation is visible. If a fruiting body is visible, this means that the wood is already heavily damaged. Certain species of fungi favor areas which are protected from drafts. This allows them to remain, for instance, for long periods behind wall panels, below floors and in roof spaces before being discovered. In cases of invisible infestation this can be indicated by, for example, sagging floorboards, a mold-like or musty odor and/or dust from spores on surfaces. In addition to this, mycelia can survive dry periods – around two years, for example, in the case of dry rot – and spores can remain germinable for many more. If increased humidity then recreates favorable conditions the spores will re-germinate and the mycelia will spread. For this reason, wood-destroying fungi can return to damage an area which has already been treated if that treatment was inadequate and not all spores and mycelia were killed [Berg 2010]. The decomposition behavior of wood-destroying fungi The decomposition behavior of wood-destroying fungi is a specific characteristic of each species and fungi are differentiated in terms of the type of rot they cause. Brown and white rot and, to a lesser degree, soft rot are relevant for buildings. These are shown in Table 16 together with the various types of fungi. Simultaneous infestations with several fungi which demonstrate differing decomposition behaviors can occur [Zwiener 2012].

Type of decomposition

Appearance

Type/group of fungus

Brown rota: Decomposition of cellulose and hemicellulose, Modification of lignin

Brown color, decomposes parallel and perpendicular to the fibers, wood breaks up upon contact into die-shaped pieces and, when the infestation is more advanced, into powder

- - - - - - -

Dry rot (Serpula lacrymans) Cellar fungus (Coniophora spp.) Mine fungus (mostly white mine fungus: Antrodia) Mazegills (Gloeophyllum spp.) Brown rot agents with lamella, e.g. rollrims or oyster rollrim (Paxillus or Tapinella panuoides) Leucogyrophana spp. Wild dry rot (Serpula himantioides)

White rot: Simultaneous rot, e.g. simultaneous decomposition of lignin, cellulose and hemicellulose into almost equal parts

Wood becomes soft, much lighter, decomposes parallel to the fibers, weight loss

- - - - -

Filamentous fungi (Donkioporia expansa) White rot agents with lamella, e.g. oyster mushrooms (Pleurotus spp). Asterostroma spp. Trechispora spp. Layer and crust fungi, e.g. non-succulent crust fungus (Hyphoder- ma praetermissum) 3

Soft rot: Decomposition of cellulose and hemicellulose. Requires constant humidity or contact with the ground. Also possible inside buildings in cases of continuously higher humidity of wood but plays a secondary role in therms of damage to internal spaces.

Similar to brown rot, breaks up into die-shaped pieces, dark, black or silver color. Musty to greasy on humid surfaces

- Sac fungi or Ascomycetae: Chaetomium - Imperfect fungi or Deuteromycetes (Funghi imperfecti: Phialo phora, Paecilomyces, Trichoderma)

Tab. 16: Decomposition behavior of wood-destroying fungi (after [Berg 2010], p. 300 ff.) 3

Predominantly white rot

The identification of and sources and causes of wood-destroying fungi – preparation of abatement measures In order to definitively identify types of fungi and the causes of infestation and to evaluate this infestation and prepare and implement abatement measures, detailed knowledge about wood-destroying fungi and about how they live, grow and spread as well as about building construction and building physics are essential. This is why such tasks should be placed in the hands of qualified specialists, companies or experts and, if required, historic buildings experts. This work is also subject to all national legal requirements regarding the protection of wood in building and the abatement of infestations of fungi and insects, such as those set out in ÖNORM B 3802-4 or DIN 68800-4. In the absence of national regulations the above norms can be used to orient abatement and decontamination measures.

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Basics First of all, a site visit is required in order to identify the location where humidity enters the building. This will require the examination of the building envelope in general and, in particular, of seals, roofs, elements which remove rainwater or critical parts of the geometry of the building (corners, valleys, connecting elements, etc.). Potentially affected areas can be inspected more closely via: • the opening up and visual control of elements of construction, • the mechanical testing of the condition of the wood (e.g. by tapping and, if necessary, by measuring the drilling resistance) and, in particular, the evaluation of the stability of structurally important elements, • the detailed investigation of masonry and jointing and, if necessary, the removal of individual bricks or blocks plus the control of plaster, sidings, cavities (in special cases where dry rot is suspected) and/or, • endoscopic testing if a damage-free analysis of the building fabric is required (in special cases where the historic buildings authorities are involved) Fungi can be identified on the basis of the macroscopic characteristics of the fruiting bodies or, in the absence of a fruiting body, the mycelia. An additional microscopic or molecular-biological analysis is also often required in order to definitively identify the type of fungus. This is particularly common when the affected timber is already heavily decomposed and fruiting bodies and mycelia are no longer available for microscopic analysis. The success of this analytical method is, however, dependent upon enough of the DNA of the fungus being present in the wood [Berg, 2010]. The abatement of wood-destroying fungi There follows a partial description of abatement measures against wood-destroying fungi in line with ÖNORM B 3802-4. Such measures must also take into account user and employee protection requirements. The key steps are: • the opening up of the building element and mechanical removal of the fungus – which means the removal of all pieces of wood in an area clearly larger than that affected by the infestation and, where necessary, the killing of the fungus with chemicals or heat treatment • the reconstruction of these elements and, if necessary, reestablishment of load-bearing capacity • if necessary, preventative chemical wood protection – especially in structurally stressed areas (e.g. heads of beams) • constructional, energy and/or technical refurbishment – which means the long-term removal of the source of humidity and, where necessary, the drying out of soaked areas • technically correct disposal – ideally through burning – in order to minimize the risk of a further infection of buildings, building elements or materials A special case is presented by dry rot which is particularly hard to fight for the following reasons: • • • • •

It grows in a concealed manner in areas protected from drafts less humidity in the wood is required for growth as a result of which mycelia can live for longer it spreads not only on wood but also masonry, fill material or drains and pipes mycelia threads can be very long (reaching several meters from the source of the humidity) the thick surface mycelium impedes the drying out of the affected area [Zwiener 2012].

In cases of dry rot infestation additional or alternative measures must be taken including a much broader search of the elements and spaces adjacent to the affected location and the treatment of these locations with chemicals and a hot flame as explained in detail in ÖN B 3802-4.

The introduction of harmful substances in new building products Following the removal of harmful substances from the building further harmful substances can be introduced to the building in new products used in additional (thermal) refurbishment measures, alterations and other renovation work. Emissions from floor finishes and the adhesives used for these finishes, wood and wood products, paints and coatings, sealing compounds and other adhesives, insulating material, cleaning and care products can contain many volatile organic compounds (VOC) such as aldehyde, ketone, styrene, glycol compound, isothiazolinone or terpene. These emissions mostly affect health via such nonspecific symptoms as indisposition and headaches, etc., which can be triggered by a range of materials. In addition to this, some materials have irritative and/or sensitizing, reproductive toxic, mutagenic and/ or carcinogenic effects. Furthermore, new building products could also contain ingredients which are relevant in terms of environmental or human toxicology such as biocides, softeners and heavy metals and their use could release reaction or decay products which are detectable as secondary emissions in the internal ambient air. For this reason, building products selected for refurbishment projects should be free of harmful substances or, where this is not possible, have low levels of harmful substances and, in particular, emissions. According to [Zwiener 2006], the term “low-emission” building products has yet to be generally defined. However, certification programs for building products have concrete requirements with regards to the emission performance of building products.

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Basics Table 17 shows the limiting values for emissions established by several product certification systems for the product group ‘floor finishes from wood or wood products’.

Limiting values for emissions for floor finishes from wood or wood products (mg/m³) Blauer Engel natureplus

Nordic Ecolabelling

Total of volatile organic compounds within the retention range C 6 – C 16 (TVOC)

after 3 days after 28 days

≤3 ≤0,3

≤ ≤0,3

Total of semi-volatile organic compounds within the retention range > C 16 – C 22 (TSVOC)

after 3 days after 28 days

– ≤0,1

≤0,1 – ≤0,1 ≤0,1

Tab. 17: Limiting values for emissions for floor finishes from wood or wood products according to the certification guidelines of the environmental labels Blauer Engel (RAL-UZ 176 2013), EU Ecolabel (2009), natureplus (2015) and Nordic Ecolabelling (2014). Testing methods ISO 16000-9 etc.

– ≤0,3

In order to evaluate internal ambient air quality the Committee for Internal Space Guidelines of the German Federal Environment Agency developed guiding values. These are hygienically-based values for evaluating a material or group of materials for which there are no toxicologically-based reference values. Table 18 shows guiding values for the total of volatile organic compounds (TVOC) in internal ambient air (Ad-hoc-AG IRK/ALOG 2007).

TVOC Value Evaluation of the TVOC Values 0,3–1 mg/m³

hygienically unproblematic hygienically still unproblematic

Target value for new and newly refurbished buildings As long as no reference value is exceeded for an individual or group of materials. Necessity of more ventilation

>1–3 mg/m³ hygienically conspicuous

An upper limit limited to 12 months for social spaces which are used for longer periods. Long-term concentrations of >1 mg/m³ are to be avoided. It is recommended to severely lower the TVOC concentration within six months.

>3–10 mg/m³ hygienically problematic

The room should either not be used at all or used in a limited way (max. 1× in month) and with increased ventilation. Reduction of the value 10 mg/m³ hygienically unacceptable

The room should either not be used at all or used in a very limited way (a few hours) and with increased ventilation. For values >25 mg/m³ the use of the room is basically to be avoided.

Tab. 18: Evaluation of the contamination of internal ambient air using reference and guiding values in line with Ad-hocAG IRK/ALOG (2007)

These guiding values are reflected differently in the criteria catalogs of the building evaluation systems. Table 19 shows the evaluation by these building evaluation systems of TVOC concentrations in internal spaces. If minimum standards are not met then – depending upon the evaluation system – either no evaluation points are awarded or the criterion is regarded as not met. In addition to this, some certification programs have introduced a stepped system for evaluating TVOC concentrations and defined a target value which allows the highest number of points to be achieved. Points are given proportionally for intermediate values. If the target value is met the maximum number of points is awarded. TVOC Concentrations BREEAM BNB* klimaaktiv*

Tab. 19: Minimum requirements and target values for TVOC concentrations in the ambient air according to the criteria catalogs for office/service buildings of the building evaluation systems BREEAM (2015), BNB (2013), klimaaktiv (2014), LEED (2014) and TQB (2010). Testing methods: DIN EN ISO 16000-5, -6, -3 (BNB), ÖN M 5700 (klimaaktiv and TQB), ISO 16000-6 etc. (LEED). Durations varied. * Stepped evaluation system for TVOC concentrations

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LEED

TQB*

Minimum requirement

0,3 mg/m 3

≤3 mg/m 3

≤3 mg/m 3

≤0,5 mg/m 3

≤3 mg/m 3

Target value

0,3 mg/m 3

≤0,5 mg/m 3

≤0,3 mg/m 3

≤0,5 mg/m 3

≤0,3 mg/m 3

Experience shows that a higher quality of interior ambient air can be achieved if zero or very low emission building products are consistently used. The selection of suitable products is helped by environmental labeling which take the previously described internal ambient air indicators into consideration in its criteria. Information about building products relevant for the internal spaces can also be found on product databases such as baubook.info or the DGNB Navigator. In order to ensure that future changes to a building can be carried out in a way which preserves the substance of the building and is carried out as expertly as possible in the interests of the users, those carrying out the work and the environment, a complete declaration that can also be retrieved in the future is desirable. Building evaluations include such documentation. In addition to this, the labeling of individual building materials and, hence, the traceability of their ingredients and treatment is also necessary.

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Basics The disposal of typical demolition materials Refurbishment work is often associated with the demolition or dismantling of building elements or constructional layers. From the ecological point of view, one objective must be the highest possible quality of recycling of the demolition material. This also applies to thinking about the later disposal of the building materials used in the refurbishment work discussed in this book. The ability to recycle a concrete share depends upon the material quality of the input. Thus, successful recycling requires the best possible separation during demolition work on site. Recycling-oriented demolition refers to demolition work which is carried out in such a way that a high proportion of the material produced as the building element is demolished or the constructional layer is removed can be recycled. The demolition process basically reverses the construction/assembly process. Regardless of all categorization, demolition will firstly be defined by accessibility (the directly accessible materials are removed first). The evaluation of the recyclability of building materials in this book is always based on the notion of recycling-oriented demolition. Mineral building materials represent by far the largest share of the mass of a building. The recycling of mineral building elements (e.g. prefabricated concrete elements) is basically possible although it should be assumed that will be in the form of material reutilization. In this process, the mineral building waste is crushed in stationary or mobile treatment units and – depending upon its basic ingredients and grain dimensions – reused as either gravel, sand or powder substitute in a wide range of applications. The quality criteria for recycling materials are defined e. g. by the Austrian Building Material Recycling Association (BRV). If they can be removed uncontaminated by other materials, gypsum plasterboard panels can be reused as materials in the production of new gypsum plasterboard panels. In practice, however, the recycling of gypsum plasterboard panels has yet to become established in Austria. It is assumed that a high proportion of the material in good-quality load-bearing timber structures will be reused or recycled. This can be reused as intact structural timbers or recycled in garden or landscape construction. Such material reutilization of constructional and demolition timber should, however, be limited to timber which has been sorted out by species and not been treated with harmful substances. It should be preventatively assumed that the following contain a high level of heavy-metal or wood protection agents: • timber elements such as windows, window sills and external doors which are usually treated with wood protection agents • timber elements such as timber floors and parquets which are usually sealed • accessible timber elements such as façade sidings, internal wall sidings and exposed beams which are exposed during normal use If the reuse or recycling of the demolition share is not possible it must be used as a source of energy, incinerated or disposed of on a waste disposal site in a permitted way. According to the Austrian Disposal Decree, the disposal of waste with high levels of organic carbons (e.g. TOC over 30 mg/kg dry mass for building waste mass in Austria) on waste disposal sites is forbidden. Given these conditions, most mineral building materials can be disposed of in such a way without difficulty. For certain mineral building materials with a potentially high level of organic components (e.g. wood wool panels, mineral wool insulating materials) the Austrian Disposal Decree envisages an exception: these can be disposed of on a disposal site without providing proof of their TOC content. In Germany, for instance, it is recommended that pure wood wool panels are incinerated although they can also be disposed of on a disposal site as part of a building waste material share (after, if necessary, preliminary treatment in order to reduce the level of organic carbons). Synthetic materials, timber and other renewable raw materials consist of organic carbons as a result of which they are generally not disposed of on disposal sites. These generally have high calorific values, which makes them fundamentally suitable for thermal recycling in incineration or waste incineration plants.

Sources: Mötzl 2009, Schneider 2010

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Basics The reconstruction of the original appearance or new design accents Formal solutions to refurbishment projects in general and thermal refurbishment using passive house components in particular repeatedly cause intense controversy. The following architectural and historical comments could help in such situations: A chronology of architecture: The period between 1900 and 1945 was dominated by the late Wilhelminian style or the regional historicist modernism of the Heimatschutzstil together with Jugendstil, art deco and expressionism, with their own design principles, extensive use of ornament and elaborate façades. From about 1920 these were replaced by the classical modernism of the New Objectivity and the International Style with its stripped-down white cubes. The post-war years were dominated by the economic austerity which led to the often unambitious architecture of the years of reconstruction and it was only after 1970 that postmodern architecture heralded a re-newed interest in outward appearance. Proportions: The classical modern restructured the proportions of buildings in line with the simple cube and a new set of proportional relationships between bodies, surfaces and openings. In the absence of decoration and ornament the construction of edges and joints gain a new central importance. Window level front/rear, externally flush – lower floor heights initially lead to smaller windows (1900 until approx. 1955) before new expectations and such technical advances as the composite and single-pane window mean that window areas grow again. Double glazing dominates after the mid-1980s – single-pane windows with double glazing and a tilt-and-turn fitting – and the first plastic windows are used. The new windows rarely have glazing bars or toplights and are often horizontal. In concrete buildings and the buildings of the years of reconstruction, reveals become smaller and windows are mostly positioned in the center of the wall. Only with new brick formats and special window reveal bricks are windows more deliberately positioned in walls and tend to move outwards. Whether the recreation of the original appearance should be a goal of refurbishment projects should be separately judged for each building. Balcony panels, balustrades, decoration and colors are important secondary design elements which support the main proportions of volumes, surfaces and openings. Hence, when refurbishment projects seek to recreate something close to the original, the design of these elements is essential to the desired result. The selection of materials should also take the original intention and material choice into account. Many detailed solutions are often rejected for economic reasons. In the case of many buildings from the 1950s to the 1970s, new proportional relationships and the selection of new colors and materials can refresh the architectural appearance.

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Building tasks

3 Building tasks This chapter will cover existing 19th and 20th century buildings (up to the 1980s) from the Central European region with an emphasis on Germany and especially Austria.

Buildings erected up to 1918

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Buildings erected from 1920 to 1950

131

Buildings of the 1950s and 1960s

137

Buildings of the 1970s

148

Buildings of the 1980s 173

Notes Peripheral insulation of unheated basements: Rather than insulating the element between the heated building and the unheated basement, the basement itself is vertically and/or horizontally insulated (dimension >= 1 m, thickness approx. 10 cm). Peripheral insulation of buildings without basements: Rather than insulating the element between the heated building and the ground, the ground at the periphery of the building is vertically and/or horizontally insulated (dimension >= 1 m, thickness approx. 10 cm).

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Building tasks Buildings erected up to 1918 The time period for pre-1918 buildings extends quite far back; in Central Europe there are still buildings (churches, but not only) that were erected well over 1,000 years ago. The majority of these structures, however, were built during the era of industrial expansion as of approx. 1860, which is called the Gründerzeit. This period will be the center of focus. The construction style is not all that different from the previous eras (e.g., Baroque); however, a tendency towards rationalization is unmistakable. The stock of pre-1918 buildings is proportionally large. According to Austrian statistics, it amounts to 353,379 buildings out of a total of 2,046,712. This means that 17% of all edifices were erected before 1918 (Statistik Austria 2004). In housing construction, a large number of multi-story buildings were especially built in the big cities for the people moving from the countryside into the city. These structures were built mostly in a coupled and very dense manner (perimeter developments). The street façades were executed with more or less ornamentation (cornices, figures, small balconies); the courtyard sides were simply plastered or the masonry was even left bare. In addition to these buildings for the newly rising working class, villas and town houses were erected in the suburbs and on the countryside for the middle class and entrepreneurs who had become affluent. The nobler of these buildings stand alone; others are built in coupled construction. Many of these structures feature more than one story. Ordinary citizens and tradesmen could “only” afford one-story buildings that were frequently constructed in a coupled way, and were similar in shape and cubature to the construction method in villages (“street villages”). In many cases, commercial activities took place in the rear area of the building (as they often did in farmhouses).

Depending on the region, natural stones were used above all in the basement area (moisture protection), whereby the interior side was also walled with bricks. To a lesser extent, especially with basement walls, a cavity wall, filled in with rubble and fill between the two brick bonds on the outside and inside, was also usual. Particularly in rural areas, a mixed construction form (demolition rubble, etc., mixed with solid brick) was also common to save fired bricks. The walls were plastered inside with lime plaster and most of the time outside as well in several layers. The plaster thicknesses were high (interior between 2 and 3 cm, exterior between 2 and 5 cm). In this book, the brickwork is depicted in the Old Austrian format size of 29 x 14 x 6.5 cm. However, the masonry thicknesses are indicated most of the time in the tables approximately in the usual thicknesses (e.g., masonry 30 cm and not 29 cm). The thickness of the supporting external walls – built mostly parallel to roads – was tapered from bottom to top in order to save material. Basement walls in multi-story buildings were between 60 and 80 cm thick, while thicknesses of 44 cm were usual in the uppermost inhabited floor and 30 cm on the top story. In most cases, the firewalls are approx. 25–30 cm thick (depending on the format). The building stands on widened foundations.

Basement – solid brick masonry, externally plastered in the area in contact with the outside air

People lived almost exclusively on the stories aboveground; the basement (or partial basement) was reserved for storage as well as for the “dehumidification” of the ground floor. The top floor was likewise uninhabited and mostly executed as a pitched roof. As far as the building method goes, it is a mixed construction consisting of solid external and internal walls as well as basement walls and ceiling slabs, and light intermediate floors and roof.

The bricks are often left exposed on the basement side. Solid brick masonry, plastered on both sides

Characterization of the existing building stock • External walls of solid brick masonry, 25 cm to over 100 cm, partially mixed masonry or natural stone masonry • Half-timbered building, originally often sided • Decorative plaster ornaments or clinker façade mostly on the street side • Basement ceilings are vault or cap vault ceilings • Timber beam or solid log floors above the basement • Double casement windows or windows with single-paned glass depending on the region

Plaster thicknesses can strongly vary.

• Large story heights • In larger cities in coupled construction or in perimeter development

External walls and external walls in contact with the ground In most cases in the Gründerzeit, the external walls were built with solid bricks, whereby the brickwork differs depending on the region. The bricking up was carried out mostly with lime mortar. According to [Atlas 2008], lime, which hardens in connection with air, was particularly used for this purpose. The mortar on the interior of the walls thus hardened slower.

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Plaster thicknesses can strongly vary.

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Buildings erected up to 1918 In order to keep the height of the ceiling between the supports and the arch rise low, the vault is graduated. Transverse arches and steel beams serve as supports. The distances between the steel beams range from 1 to 2.5 m. For the most part, the ceilings are plastered on the lower side.

Floor in contact with the ground

A 30-cm-thick wall is usual for firewalls and on the top floor (jamb wall).

Plastered limestone masonry

Floors in contact with the ground were generally tamped clay floors or they were covered with brick paving. When problems with the stability of the subfloor occurred, tamped concrete was also used, partially on top of wooden stakes driven into the earth. Buildings without or with only a partial basement also had a tamped clay floor as the bare floor, upon which a fill (gravel, slag, building waste) was applied, which the raft battens were then driven into. Timber floor-boards were directly laid on top. Depending on the usage of the space above, parquet floors were also laid upon subfloors. In hallways, etc., stone slabs or paving bricks were also implemented. Floor in contact with the ground

The thickness of the wall is adapted to the structural requirements. Depending on the location, a row of different stones is usual. Sometimes these stones are also exposed on the outside in a regionallyspecific manner.

Basement ceiling slabs For moisture protection reasons, basement ceiling slabs were solidly built in most cases. Structurally, most of these were vaulted ceilings; as of the turn of the 19th century, they were frequently only built as a partial vault (cap vault ceiling).

Sometimes the old floors had been subsequently covered with PVC sheets (kitchens, anterooms), which often caused the timber substructure to rot.

Vaulted ceiling

Internal walls Load-bearing internal walls are executed for the most part like the external walls; slightly higher wall thicknesses mostly result. In many cases, the chimneys are also integrated. Lime mortar, sometimes with slight additions of cement, was generally used for the bricking up. For the non-load-bearing walls, either solid bricks or stones were likewise used. From the turn of the century onwards, lighter stones were increasingly utilized (e.g., slag bricks), as well as timber constructions filled in with cob or clay. Nailed plaster baseboards were plastered with lime mortar.

The actual construction of the vault varies over the centuries. Depending on the execution, relevant horizontal shear stresses arise, which have to be absorbed in the basement masonry in part with additional supports. Sand, slag, but also building rubble is used as fill.

Load-bearing solid brick internal wall

Cap vault ceiling

Masonry thicknesses can strongly vary. The load-bearing basement internal walls are usually not plastered.

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Building tasks Non-load-bearing solid brick wall

Alternatively, slag bricks, etc., were also used instead of solid bricks.

Plastered solid brick masonry, chimney

Depending on the span width and location, the timber beams are placed at distances between 60 and 100 cm. Timber cladding was laid on the upper side. To keep the fill material from leaking downwards, timber battens were nailed on or the cladding was connected with tongues. Sand, slag, but also building rubble was used as fill. In addition to having a leveling function, they also provided fire and noise protection. Raft battens were driven into them; timber floorboards or subfloors with parquets were laid on top. Timber cladding was usually nailed onto the lower side; on top of it, reed lath and plaster served as a plaster baseboard, which was plastered with lime mortar. Sometimes the timber cladding was also left out. The end surface could also be wood paneling.

Top story ceilings The top floor leads most of the time into an unused roof space, which was executed as a “cold roof” and was more or less rear-ventilated with outside air. In many parts of Central Europe, timber beam ceilings were also constructed as the top story ceilings. In the East Austrian region, solid log floors were frequently built in the Gründerzeit era. Timber beam ceiling

Most of the time, the chimneys were built in the load-bearing middle wall, which was likewise tapered towards the top. Non-load-bearing plastered limestone internal wall

The structure is similar to an intermediate floor. On the upper side, paving bricks are laid on the fill for fire prevention reasons. Solid log floor

Alternatively, blocks made of slag, pumice concrete, clay, etc., were applied instead of solid bricks.

Intermediate floors Intermediate floors in Gründerzeit houses were mostly constructed as timber beam ceilings, which can differ in the detail features. In rare cases, the ground floor ceiling was still built as a cap vault ceiling. As of the 19th century, solid ceilings (reinforced concrete slabs) occasionally appear on the upper stories as well. Timber beam ceiling

The logs used for the solid log floor are only edge-trimmed on two sides and doweled together. A sand or slag fill is applied on the upper side, which is covered with brick paving stones. The lime plaster is applied on the lower side to a reed lath and plaster baseboard. In some cases, timber cladding is additionally attached to the structural slab.

Roof Roofs from pre-1918 buildings were erected almost consistently as a carpentry construction. The complete roof truss forms a fixed system that lies upon the load-bearing walls; tie beams connect the various base areas. Most of the time, different forms of roof tiles, which are attached to the roof battens, were used for the roof covering. Metal roofs were

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Building establishes until 1900 also constructed, as well as – particularly in rural regions – roof coverings with wood shingles, straw or stone plates. Tiled roof

Defects/Types of damage The following types of damage are typical for Gründerzeit buildings: • Moisture and salt damage in rising masonry • Timber beams of the intermediate floors or the top story ceiling are rotted • Moisture damage in the eaves area • Façade: Chipping plaster or decorative plasterwork, soiled façade

Renovation tasks

The rafter thickness can range from 12 to 20 cm, the roof battens can also be 5/8 battens if the distances between the rafters are relatively large.

Windows Depending on the location, the windows are constructed as double casement windows or as windows with single casements. Most often, profiled wood frames approx. 4 cm, sometimes 6 cm thick, serve as window frames. As far as form is concerned, the windows were frequently constructed in 2, 3 or 4 parts. • the lower part was realized with 2-part windows • the upper part is single- or likewise double-leafed. A transom is arranged in-between. Especially in older buildings (Baroque Era), but also in certain regions, the outer casement of the double casement window opens to the outside. The window frame is set in a flush manner; a protection against driving rain is attached in the lintel area most of the time by means of metal sheet or a wooden board. Structurally, the lintel is usually bricked into the arches; in a few cases, steel supports are also used. Depending on the execution, the windows have a bed stop. The street façade frequently featured strongly structured ornamentation, which was realized with profiled ashlars in the window area. These also provided protection against driving rain in the lintel area and/or functioned as outwardly sloping window sills. On the interior, the reveal and lintel are plastered; in many cases they are covered with profiled timber sidings. These are often executed in the parapet area as well. In addition, wooden elements, which can be folded in front of the windows and thereby offer additional heat insulation in the winter, can be executed in the reveal.

• Exterior insulation, possibly with reconstruction techniques for decorative plasterwork and structuring of the façades • Interior insulation with particular attention to the joints • Inclusion of the stairwell (mezzanine problem) • Insulation of the top story ceiling; accessible, non-accessible; joints of the eaves • Possible loft conversion, new terraces • Window renovation, partially with special double casement windows, joints • Insulation of the basement ceiling slab, minimization of thermal bridges across external walls and internal walls • Construction of new balconies on the courtyard side • Moisture protection against driving rain, rising dampness • Improvement of airtightness • Improvement of acoustic insulation to the outside (windows and window junctions) • Improvement of acoustic insulation between living units (walls, ceilings) • Improvement of fire protection between the living units • Optimized room ventilation

Double casement window

Illustration of a double casement window without a lintel.

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Building tasks Details base: External wall – basement ceiling slab D01 | External wall with ETICS – insulated external wall in contact with the ground – uninsulated basement ceiling slab

1

Suitability • When exposure to rising damp and efflorescence is low (see page 26) Construction process • S eal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the vertical seal.

• Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

• Excavation depth depending on the structural possibilities • Tightly bond the seal on the complete surface up to 30 cm above ground level

Existing building stock: Plastered solid brick external wall – basement with brick vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description The existing building stock will be thermally renovated by means of an horizontal perimeter insulation. The basement ceiling slab remains uninsulated; the external walls of the basement are insulated: • As a result of the horizontal perimeter insulation, the temperature of the basement room rises in the winter; if the moisture source remains constant, there will be a lower relative humidity, meaning advantages for storage. Basement room temperatures will also be lower in the summer. Therefore, a combination with intelligent basement ventilation makes sense (see section on building components in contact with the ground). • If the masonry is penetrated with moisture through surface water, the absorption can be stopped by applying the vertical seal and draining the masonry.

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Buildings erected up to 1918

D02 | External wall with insulation between the timber construction – external wall in contact with the ground, horizontally sealed and insulated

Suitability • When exposure to rising damp and efflorescence is high (see page 26) • Need for drainage (see page 21) Construction process • E xcavation depth depending on the structural possibilities • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. Bituminous slurry is to be used in the seal area.

• Tightly bond the seal on the complete surface up to 30 cm above ground level • Bond and mechanically secure the drip edge to the end of the timber construction • Bond the ECB membrane on the lower end of the timber construction (OSB panel) • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

Existing building stock: Plastered solid brick external wall – basement with brick vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description The existing building stock will be thermally renovated by means of an horizontal perimeter insulation. The basement ceiling slab remains uninsulated; the external walls of the basement are insulated. An horizontal perimeter insulation offers several advantages: • As a result of the horizontal perimeter insulation, the temperature of the basement room rises in the winter; if the moisture source remains constant, there will be a lower relative humidity, meaning advantages for storage. Basement room temperatures will also be lower in the summer. Therefore, a combination with intelligent basement ventilation makes sense (see section on building components in contact with the ground). • If the masonry is penetrated with moisture through surface water, the absorption can be stopped by applying the vertical seal and draining the masonry.

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Building tasks D03 | External wall with insulation between timber construction – cap vault ceiling, insulated on the upper side with fill

Suitability • If exposure to rising damp and efflorescence is low (see page 26) • If the ground floor apartment can be vacated for the renovation • Need for drainage (see page 21)

insulation panel should be completely bonded. The insulation should reach at least 0.5 m below the ground level. • If only existent in parts, extend the existing interior plaster as an airtight layer up to the structural slab. • Insert and compact perlite fill, place wood fiberboard on top

Construction process • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the vertical seal. • After mounting the external wall insulation system, extend the seal layer all the way to the drip edge and bond it to the heel (e.g., with an ECB membrane). • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top

• Consider the use of an intelligent ventilation system for the basement (see page 26 and 69) Discussion Particularly suitable for “dry” basements with moisture reserves, where no high requirements are placed on the moisture behavior. The vapor-permeable structure of the external wall insulation enables the (low) quantities of moisture to still be conducted to the outside.

Existing building stock: Plastered solid brick external wall – basement with brick vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description The existing stock will be thermally renovated by means of an exterior and perimeter insulation and an insulation of the basement ceiling slab on the upper side. • The continuous airtight layer is the exterior plaster and the vapor barrier of the basement ceiling slab. A direct airtight connection of the vertical and horizontal layer is not possible. • The thermal bridge effect in the base area is high. • Through the thermal insulation of the basement ceiling slab, the temperature in the basement is lowered and, without accompanying measures, the relative humidity in the basement is increased.

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Buildings erected up to 1918

Details base: Internal wall – basement ceiling slab D04 | Plastered solid brick internal wall – basement ceiling slab insulated on the upper side

Suitability • If exposure to rising damp and efflorescence is low (see page 26) • If the ground floor apartment can be vacated for the renovation Construction process

• Lay the vapor barrier; make an airtight connection with the interior plaster • Consider the use of an intelligent ventilation system for the basement (see page 26 and 69)

• Remove floor structure and fill

Discussion

• If only existent in parts, extend the existing interior plaster as an airtight layer up to the ceiling slab

Particularly suitable for “dry” basements with moisture reserves, where no high requirements are placed on the moisture behavior.

• Insert and compact perlite fill, add wood fiberboard

Existing building stock: Plastered solid brick internal wall – vaulted basement ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? Description The existing building stock will be thermally renovated by means of thermal insulation on the upper side of the basement ceiling slab. • The continuous airtight layer is the exterior plaster and the vapor barrier of the basement ceiling slab. A direct airtight connection of the vertical and horizontal layer is not possible. • The thermal bridge effect in the base area is high. • Through the thermal insulation of the basement ceiling slab, the temperature in the basement is lowered and, without accompanying measures, the relative humidity in the basement is increased. • The insulation height strongly depends on the existing floor level. High insulation thicknesses are frequently not possible. As a whole, the attainable thermal insulation is thereby limited

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Building tasks Details Base: External wall – floor in contact with the ground D05 | External wall with ETICS – floor in contact with the ground, insulated on the upper side

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the ground floor apartment can be vacated for the renovation • If perimeter insulation is possible (statics, surface structure) Construction process • C lean the exterior plaster and base; repair the missing pieces and extend the seal to the lower edge. The exterior plaster provides the airtight layer and clean surface for applying the vertical seal.

• Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. Extend the perimeter insulation up to 1 m below the ground level, if possible. • Remove the existing floor, dig down to desired depth, lay the hardcore base, apply weak concrete blinding onto the separating layer, completely seal the entire surface; connect it to the extended interior plaster if necessary.

Existing building stock: Plastered solid brick external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by insulating the outer side of the external wall, whereby the perimeter insulation is extended as far downwards as possible, ideally to the lower edge of the foundation. • The floor will be insulated on the upper side; a weak concrete blinding will be used as a permanently sustainable base for the seal and pressure-resistant insulation. • Possibly lower the ground level, at least in the splash zone, and especially in the door area, if required. • The thermal bridge effect in the base area is high.

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Buildings erected up to 1918

D06 | External wall with ETICS – floor in contact with the ground, insulated on the lower side

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the ground floor apartment can be vacated for the renovation • If perimeter insulation is possible (statics, surface structure)

• Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. Extend the perimeter insulation down to 1 m below the ground level, if possible. • Remove the existing floor, dig down to desired depth

Construction process • C lean the exterior plaster and base; repair the missing pieces and extend the seal to the lower edge. The exterior plaster provides the airtight layer and clean surface for applying the vertical seal.

• Insert the hardcore base, lay the weak concrete sub-floor blinding on the separating layer and XPS, apply weak concrete blinding onto the separating layer, fully seal it, connect it to the possibly extended interior plaster

Existing building stock: Plastered solid brick external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by insulating the outer side of the external wall, whereby the perimeter insulation is extended as far downwards as possible, ideally to the lower edge of the foundation. • The floor will be insulated on the lower side. • Possibly lower the ground level, at least in the splash zone, and especially in the door area, if required. • The thermal bridge effect in the base area is high.

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Building tasks D07 | External wall with ETICS – horizontal perimeter insulation – uninsulated floor

3

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the floor cannot or doesn’t have to be replaced Construction process • C lean the exterior plaster and base; repair the missing parts. The exterior plaster provides the airtight layer and clean surface for applying the vertical seal. • Concrete the reinforced weak concrete sub-floor blinding onto the hardcore base; structurally attach it onto the base in places. • Tightly bond the seal on the complete surface up to 30 cm above ground level (splash zone) and attach a gravel stop.

• Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge. • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. The depth of the horizontal perimeter insulation should extend down to 1 m below the ground level, if possible. • Wrap the drainage gravel bed on all sides with PP filter fleece; carefully avoid getting soil on the gravel while working.

Existing building stock: Plastered solid brick external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by insulating the outer side of the external wall; the floor remains uninsulated. The horizontal perimeter insulation will be executed on a lean concrete sub-floor blinding statically affixed on the foundation. • The constant habitability of the ground floor apartment is an advantage. • Possibly lower the ground level, at least in the splash zone, and especially in the door area, if required.

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Buildings erected up to 1918

D08 | Limestone external wall with ETICS – floor in contact with the ground, insulated on the lower side

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the ground floor apartment can be vacated for the renovation • If perimeter insulation is possible (statics, surface structure) Construction process • Clean the exterior plaster and base; repair the missing pieces and extend the seal to the lower edge. The exterior plaster provides the airtight layer and clean surface for applying the vertical seal. • Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation

of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge. • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. The depth of the horizontal perimeter insulation should extend down to 1 m below the ground level, if possible. • Insert the hardcore base, lay the weak concrete sub-floor blinding on the separating layer, XPS; apply weak concrete blinding onto the separating layer, completely seal the entire surface, bond to the extended interior plaster if required.

Existing building stock: Plastered limestone external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by insulating the outer side of the external wall, whereby the perimeter insulation is extended as far downwards as possible, ideally to the lower edge of the foundation. • The floor will be insulated on the lower side. • Possibly lower the ground level, at least in the splash zone, and especially in the door area, if required. • The thermal bridge effect in the base area is high.

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Building tasks Details Base: Internal wall – floor in contact with the ground D09 | Solid brick internal wall – floor in contact with the ground, insulated on the upper side

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the ground floor apartment can be vacated for the renovation Construction process • Remove the existing floor, dig down to desired depth • Insert the hardcore base, apply weak concrete blinding onto the separating layer, completely seal the entire surface, connect it to the extended interior plaster if necessary.

Existing building stock: Plastered solid brick internal wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? Description of the renovation The existing building stock will be thermally renovated by insulating the outer side; a weak concrete blinding will be used as a permanently sustainable base for the seal and pressure-resistant insulation. • The thermal bridge effect in the base area is high. However, it also depends on the compactness of the building, the execution of the horizontal perimeter insulation, etc.

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Buildings erected up to 1918

D10 | Solid brick internal wall – floor in contact with the ground, insulated on the lower side

Suitability • If exposure to rising damp and efflorescence is low (see page 41) • If the ground floor apartment can be vacated for the renovation Construction process • Remove the existing floor, dig down to desired depth

• Extend the existing interior plaster as an airtight layer to the weak concrete sub-floor blinding; lay pressure-resistant and moistureproof thermal insulation, pour concrete slab • Completely seal the entire surface, seal it airtight on the interior plaster

• Insert the hardcore base, apply weak concrete sub-floor blinding onto the separating layer

Existing building stock: Plastered solid brick internal wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? Description of the renovation The existing building stock will be thermally renovated through a pressure-resistant, moisture-proof, lower-sided insulation of the floor in contract with the ground. • The moisture behavior of the floor construction is an advantage: The installations can be laid on the warm side; the seal lies in the warm area. • The thermal bridge effect in the base area is high. However, it also depends on the compactness of the building, the execution of the horizontal perimeter insulation, etc.

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Building tasks Details Intermediate stories: External wall – intermediate floor D11 | External wall with ETICS – intermediate floor, timber beams

Suitability • For façades without elaborate decorative plasterwork Construction process • The airtight layer is the existing exterior plaster; close the cracks; if necessary fill the entire surface.

Existing building stock: Plastered solid brick external wall – intermediate floor, timber beams Preliminary questions • Are there any cracks? Description of the renovation The existing building stock will be thermally renovated by thermally insulating the external wall on the outer side. • The temperature in the beam end area will considerably rise; at the same humidity load, the relative humidity in the front area of the beam end will sink. • A water vapor-permeable, but waterresistant plaster system will also decrease the amounts of water penetrating through driving rain.

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Buildings erected up to 1918

Details Intermediate stories: External wall – external wall D12 | External wall – plastered solid brick corner, with insulation between the timber construction

Suitability

Connection variations

• With low exposure to rising damp

Other support systems such as timber C-beams

Construction process • The airtight layer is the existing exterior plaster; close the cracks; if necessary, fill the entire surface. Discussion The vapor-permeable structure of the external wall insulation enables the (low) quantities of moisture to still be conducted to the outside. Observe local fire protection regulations.

Existing building stock: Plastered solid brick external wall Preliminary questions • Rising damp, efflorescence? Description of the renovation The existing building stock will be thermally renovated through a timber construction with timber I-beams, blown out with cellulose. • The timber construction will be mounted on site and closed on the outside with the wood fiberboard. • The exterior plaster is the continuous airtight layer. • By thermally insulating the exterior corner, the surface temperature in the corner can be significantly raised and a high degree of safety offered as a result.

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Building tasks Details Parapet: External wall – unheated roof D13 | External wall with insulation between timber construction – top story ceiling loose-fill insulation

Suitability

Discussion

• For accessible attics Construction process • F ill, plaster the jamb wall, lay the vapor barrier, repair the existing exterior plaster, connect it with the vapor barrier in the roof area • Insert and compress perlite fill; lay the pore sealing panel on top

The construction of the eaves gutter enables the proportions in the exterior area to be retained. If this is not required for design reasons, the existing construction can be replicated with an edge gutter. As a result, the external wall connection “slides” approx. 30 cm upwards. If structurally required, the perlite fill can also be directly laid onto the solid logs so that the weight of the fill and bricks can be reduced.

• Uncover the roof in the eaves area, double the rafters with fillets, lay the cladding and vapor-permeable roofing sheet, seal in a windtight manner with the pore sealing panel and exterior plaster

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is the roofing waterproof? • Use of the attic: Storage space, to dry laundry, unused? Depending on the utilization, place thermal shell in the roof or on the ceiling; take ventilation (vapor removal) into consideration Description • The cellulose insulation is blown into the timber construction; the decorative elements are made of EPS. • The top story ceiling is insulated with a perlite fill; a load distribution plate also makes the renovated attic accessible. • The airtight layer is the newly laid vapor barrier on the ceiling, which is connected with an airtight seal across the filled jamb wall to the existing exterior plaster. A continuos airtight layer is not possible only in the rafter bearing area. • As a result of the insulation, the temperatures in the attic will be significantly lowered in the winter halfyear. This is to be taken into account in the future utilization and ventilation of the attic.

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Buildings erected up to 1918

D14 | Plastered solid brick firewall – top story ceiling with loose-fill insulation

Suitability • For accessible attics • Also for renovating one apartment at a time Construction process • Fill/plaster jamb wall up to a height of approx. 1 m, lay the vapor barrier, bond it with the vapor barrier in the attic area • Insert and compress perlite fill; lay the pore sealing panel on top, connect it in a windproof manner with the jamb wall plaster

• Completely bond or dowel the perimeter insulation onto the leveling screed/plaster • If structurally required, the perlite fill can also be directly laid onto the solid logs so that the weight of the fill and bricks can be reduced. • If the firewall directly borders on another building, include the temperature zone of the neighboring structure in the renovation concept.

Existing building stock: Plastered solid brick firewall – solid log floor – tiled roof Preliminary questions • Is the roofing waterproof? • Use of the attic: Storage space, to dry laundry, unused? Description of the renovation • The top story ceiling is insulated with a perlite fill; a load distribution plate also makes the renovated attic accessible. • The airtight layer is the newly laid vapor barrier on the ceiling, which is bonded on the filled jamb wall. A continuous connection to the airtight layer of the exterior plaster of the firewall is not possible. • As a result of the insulation, the temperatures in the attic will be significantly lowered in the winter half-year. This is to be taken into account in the future utilization and ventilation of the attic (ventilation tiles, etc.).

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Building tasks Details Parapet: External wall – heated roof D15 | External wall with insulation between the timber construction – attic with rafter doubling

Suitability • For façades that can be externally insulated Construction process • Rough plaster the jamb wall, apply composite concrete, lay bituminous vapor barrier/temporary seal

• Repair the existing exterior plaster, seal it with an airtight foil onto the interior plaster base coat of the jamb wall • Double up the rafters, lay timber cladding and vapor-permeable roofing sheet. Insert the insulation, fasten the cladding, connect the vapor barrier onto the plaster base coat of the jamb wall.

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Are the rafters still statically usable? Description of the renovation • The cellulose insulation is blown into the timber construction; the decorative elements are made of EPS. • The rafters are reused, doubled up and insulated with fiber insulation. • The solid log floor, formerly the top story ceiling, is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The airtight layer is the newly laid vapor barrier in the roof that is attached in an airtight manner across the plas-tered jamb wall to the existing exterior plaster. A cleanly sealed layer is not possible in the rafter bearing area.

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Buildings erected up to 1918

Details Parapet: External wall – terrace D16 | Terrace door – terrace on concrete floor – timber concrete composite mezzanine floor

Suitability • If two different levels between the terrace and living space are acceptable

• The reduced vertical upstand of the moisture seal allowed for terrace doors requires the moisture seal to be mechanically fastened onto the window frame. Discussion

Construction process • R emove bricks and fill, apply composite concrete, lay the bituminous vapor barrier/temporary seal • Bond the top impact sound insulation step to the impact sound insulation strips

A suitable door profile, a canopy and a ramp are required for a barrierfree exit. Alternatively, the floor level inside can be accordingly raised (by increasing the fill height or by pressure-resistant insulation) at the expense of the room height.

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is the solid log floor still statically usable? Description of the renovation • The former top story ceiling becomes a terrace and separating floor of the attic extension. • The solid log floor is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The terrace door is supported on an insulated lightweight wall element; the level difference is executed by 2 steps (alternative: ramp) • The airtight layer is the vapor barrier/temporary seal laid on the composite concrete. This is connected with a vapor barrier onto the doorframe in a vaporproof and airtight manner.

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Building tasks D17 | Terrace door – terrace with vacuum insulation – timber concrete composite mezzanine floor

Suitability • If two different levels between the terrace and living space are not acceptable Construction process emove bricks and fill, apply composite concrete, lay the bitumi• R nous vapor barrier/temporary seal • To properly execute the vacuum insulation, draw upon companies with the respective expertise, since the panels are very sensitive to mechanical damage.

• Bond the top impact sound insulation step to the impact sound insulation strips • The reduced vertical upstand of the moisture seal allowed for terrace doors requires the moisture seal to be mechanically fastened onto the window frame. Discussion • It is also possible to lay single-layered vacuum insulation.

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is solid log floor still statically usable? Description of the renovation • The former top story ceiling becomes a terrace and separating floor of the attic extension. • The solid log floor is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The terrace door is supported on an insulated lightweight wall element; thanks to the vacuum insulation there is no level difference • The airtight layer is the vapor barrier/temporary seal laid on the composite concrete. This is connected with a vapor barrier onto the doorframe in a vaporproof and airtight manner.

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Buildings erected up to 1918

D18 | External wall with ETICS – top story ceiling becomes a terrace, variant 1

Suitability

• Clean exterior plaster, repair missing parts. The exterior plaster constitutes the airtight layer. Seal it airtight on the concrete grating with sealing tape.

• If the solid log floor is statically suitable Construction process • Remove bricks and fill, apply composite concrete, lay the bituminous vapor barrier/temporary seal up to the concrete grating. Plaster jamb wall beforehand, if necessary.

Discussion The higher the jamb wall, the higher the thermal bridge loss is. In this case, possibly rebuild it completely and cleanly separate it thermally.

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is solid log floor still statically usable? Description of the renovation • The former top story ceiling becomes a terrace. The solid log floor is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The existing external wall is insulated with an external thermal insulation composite system; the prefabricated EPS decorative elements are affixed. • The airtight layer is comprised of the vapor barrier/temporary seal laid on the composite concrete in the terrace area and the existing exterior plaster in the façade area. Both are bonded airtight with each other across the concrete grating.

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Building tasks D19 | External wall with ETICS – top story ceiling becomes a terrace, variant 2

Suitability

• Fasten lightweight construction element onto the concrete grating; fasten handrail onto the grating

• If solid log floor is statically suitable Construction process • R emove bricks and fill, apply composite concrete, lay the bituminous vapor barrier/temporary seal • Clean exterior plaster, repair missing parts. The exterior plaster constitutes the airtight layer. Seal it airtight on the concrete grating with sealing tape.

• Fully bond the insulation panels in the concrete grating area in order to safely exclude an upward vapor release over the air layer between the existing plaster and the insulation panels Discussion Observe the local fire protection requirements (lightweight construction element)

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is solid log floor still statically usable? Description of the renovation • The former top story ceiling becomes a terrace. The solid log floor is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The existing external wall is insulated with an external thermal insulation composite system; the prefabricated EPS decorative elements are affixed. • The airtight layer is comprised of the vapor barrier/temporary seal laid on the composite concrete in the terrace area and the existing exterior plaster in the façade area. Both are bonded airtight with each other across the concrete grating.

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Buildings erected up to 1918

D20 | External wall with ETICS – top story ceiling becomes a terrace, variant 3

Suitability

• Dowel the lightweight construction element onto the concrete grating; fasten handrail on top of it

• If solid log floor is statically suitable Construction process • Remove bricks and fill, apply composite concrete, lay the bituminous vapor barrier/temporary seal

• Fully bond the insulation panels in the concrete grating area in order to safely exclude an upward vapor release over the air layer between the existing plaster and the insulation panels.

• Clean exterior plaster, repair missing parts. The exterior plaster constitutes the airtight layer. Extend this over the concrete grating and reinforce it in this area.

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is solid log floor still structurally usable? Description of the renovation • The former top story ceiling becomes a terrace. The solid log floor is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The existing external wall is insulated with an external thermal insulation composite system; the prefabricated EPS decorative elements are affixed. • The airtight layer is comprised of the vapor barrier/temporary seal laid on the composite concrete in the terrace area and the existing exterior plaster in the façade area. Both are bonded airtight with each other across the concrete grating.

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Building tasks Details interior insulation D21 | External wall with interior insulation – basement ceiling slab, insulated with fill on the upper side

Suitability • If exposure to rising damp and efflorescence is low (see page 26) • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48) • If exterior renovation is not possible (listed building, etc.)

• Lay the vapor barrier; bond it in an airtight manner with the interior plaster • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69) Discussion

Construction process • Remove existing floor construction and fill • If only existent in parts, extend the existing interior plaster as an airtight layer up to the ceiling slab • Insert and compact perlite fill, add wood fiberboard

Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). Particularly suitable for “dry” basements with moisture reserves, where no high requirements are placed on the moisture behavior.

Existing building stock: Plastered solid brick external wall – basement with vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by means of an interior insulation on the external wall, as well as on the basement ceiling area. • The thermal bridge-free connection of the vertical insulation level with the horizontal one is an advantage. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. If there is a low moisture penetration of the masonry, sufficient moisture can be removed from the basement at a low air exchange. In the case of an increased moisture penetration of the masonry, an increased air exchange must take place in order to avoid structural damage. The insulation thicknesses are to be adapted according to the external and internal climate. • Through the thermal insulation of the basement ceiling slab, the temperature in the basement is lowered and, without accompanying measures, the relative humidity in the basement is increased (see page 26).

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Buildings erected up to 1918

D22 | Solid brick external wall with interior insulation – cap vault ceiling, insulation on lower side

Suitability • If exposure to rising damp and efflorescence is low (see page 26)

• Repair interior plaster, if necessary; fully bond and fill/plaster the insulation material

• If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48)

• Close cracks and imperfections in the plaster on the lower side of the basement ceiling slab

• If external renovation is not possible (listed building, etc.)

• Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26)

Construction process • P rotect existing exterior plaster against penetrating moisture (driving rain), close cracks, etc.

Existing building stock: Plastered solid brick external wall– basement ceiling slab Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated by interior insulation on the external wall and insulation on the lower side of the basement ceiling slab. The continuous airtight layer is the exterior plaster and the lower-sided plaster of the basement ceiling slab; a direct airtight connection is not possible. • The preservation of the existing floor is advantageous. • Through the thermal insulation of the basement ceiling slab, the temperature in the basement is lowered and, without accompanying measures, the relative humidity in the basement is increased. • The thermal bridge effect in the base area is high.

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Building tasks D23 | External wall with interior insulation – floor in contact with the ground, insulated on the upper side

Suitability • If exposure to rising damp and salt damp is low (see page 41)

• If it only exists in parts, extend the existing interior plaster as the airtight layer up to the ceiling slab.

• If the ground floor can be vacated for the renovation

• Fully apply the seal and connect it airtight onto the interior plaster

• If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48)

• Fully bond the interior insulation onto the existing building stock

• If exterior renovation is not possible (listed building, etc.) Construction process • Remove the existing floor, dig to desired depth

Discussion If a sealed surface (e.g., sidewalk) on the outside directly (without a drainage layer) connects to an external wall, form the surface with an incline leading away from the house.

• Insert the hardcore base, pour weak concrete blinding on the separating layer

Existing building stock: Plastered solid brick external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated through interior insulation on the external wall, as well as in the floor area. • The thermal bridge-free connection of the vertical insulation level with the horizontal one is an advantage. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • With an increased moisture penetration of the subsoil, a long-term functional capability of the interior insulation is not fulfilled. This type of renovation situation calls for a hygrothermal simulation, since the damage potential cannot be estimated in the planning stage.

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Buildings erected up to 1918

D24 | External wall with interior insulation – floor in contact with the ground, insulated on the lower side

Suitability • If exposure to rising damp and salt damp is low (see page 41) • If the ground floor can be vacated for the renovation • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48) • If exterior renovation is not possible (listed building, etc.) Construction process

• Embed the hardcore base, apply weak concrete sub-floor blinding onto the separating layer • Extend the existing interior plaster as an airtight layer to the weak concrete sub-floor blinding, lay pressure-resistant and moistureproof thermal insulation, pour concrete slab • Fully apply the seal and connect it airtight onto the interior plaster • Fully bond the interior insulation onto the existing building stock

• Remove the existing floor, dig to desired depth

Existing building stock: Plastered solid brick external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated through an interior insulation on the external wall, as well as a lower-sided insulation of the floor in contact with the ground. • The moisture behavior of the floor construction is advantageous: The installations can be laid on the warm side; the seal lies in the warm area. • The connection is nearly thermal bridge-free through the connection of the vertical insulation layer with the horizontal one. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • With an increased moisture penetration of the subsoil, a long-term functional capability of the interior insulation is not fulfilled. This type of renovation situation calls for a hygrothermal simulation, since the damage potential cannot be estimated in the planning stage.

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Building tasks D25 | Limestone external wall with interior insulation – floor in contact with the ground, insulated on the lower side

Suitability • If exposure to rising damp and salt damp is low (see page 41) • If the ground floor can be vacated for the renovation • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48) • If exterior renovation is not possible (listed building, etc.) Construction process

• Embed the hardcore base, apply weak concrete sub-floor blinding onto the separating layer • Extend the existing interior plaster as an airtight layer to the weak concrete sub-floor blinding, lay pressure-resistant and moistureproof thermal insulation, pour concrete slab • Fully apply the seal and connect it airtight onto the interior plaster • Fully bond the interior insulation onto the existing building stock

• Remove the existing floor, dig to desired depth

Existing building stock: Plastered limestone external wall – floor in contact with the ground Preliminary questions • Rising damp, efflorescence? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The existing building stock will be thermally renovated through an interior insulation on the external wall, as well as a lower-sided insulation of the floor in contact with the ground. • Advantageous is the moisture behavior of the floor construction: The installations can be laid on the warm side; the seal lies in the warm area. • The connection is nearly thermal bridge-free through the connection of the vertical insulation layer with the horizontal one. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • With an increased moisture penetration of the subsoil, a long-term functional capability of the interior insulation is not fulfilled. This type of renovation situation calls for a hygrothermal simulation, since the damage potential cannot be estimated in the planning stage. • This particularly applies because of the high heat conductivity of the limestone masonry.

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Buildings erected up to 1918

D26 | External wall with interior insulation – internal wall with perimeter insulation 0.5 m (horizontal section)

Discussion

Suitability • If exposure to rising damp and salt damp is low (ground floor) • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) • If exterior renovation is not possible (listed building, etc.)

Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). The depth of the perimeter insulation, 0.5 m, is sufficient. An integration of the emerging edge into the furnishing concept helps prevent mechanical damage to the edge.

Construction process • Repair interior plaster if necessary and smooth out unevenness • Fully bond insulation panels; connect new interior plaster onto old interior plaster in a permanently airtight manner • Consider the use of a comfort ventilation system with surplus extract air (see page 69)

Existing building stock: Plastered solid brick external wall – plastered solid brick internal wall Preliminary questions • Rising damp, efflorescence on the ground floor? • Apartment party wall? Description of the renovation The existing building stock will be thermally renovated by applying interior insulation and perimeter insulation on the internal wall. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • The mold risk and the thermal bridge loss can be significantly reduced by the perimeter insulation.

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Building tasks D27 | External wall with interior insulation – internal wall with tapered perimeter insulation 0.5 m (horizontal section)

Suitability

Discussion

• If exposure to rising damp and salt damp is low (ground floor) • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization)

Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). Mechanical damage to the edge can be avoided through the tapering.

• If exterior renovation is not possible (listed building, etc.) Construction process • Repair interior plaster if necessary and smooth out unevenness • Fully bond insulation panels; connect new interior plaster onto old interior plaster in a permanently airtight manner • Consider the use of a comfort ventilation system with surplus extract air (see page 69)

Existing building stock: Plastered solid brick external wall – plastered solid brick internal wall Preliminary questions • Rising damp, efflorescence on the ground floor? • Party wall? Description of the renovation The existing building stock will be thermally renovated through an interior insulation and a perimeter insulation of the internal wall. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • The mold risk and the thermal bridge effect can be significantly reduced by the perimeter insulation.

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Buildings erected up to 1918

D28 | Solid brick external wall with capillary-conductive interior insulation – intermediate floor, timber beams

2

2

Suitability

Construction process

• If penetrating moisture from outside (driving rain) can be surely ruled out (vapor-permeable hydrophobization, closing of all cracks) • If exterior renovation is not possible (listed building, etc.) • For renovating one apartment at a time • If conditions acc. to chapter internal insulation are complied with (see page 48)

• Repair exterior plaster, apply a vapor-permeable, water-resistant coating • Close cracks in the interior plaster; make an airtight connection at the foot level of the parquet floor with a vapor-permeable sheet. Even it out, if necessary. • Fully bond, plaster or fill the capillary-conductive panels. Insert expanding foam compression tape or soft insulation strips in the base area and bond them airtight onto the parquet floor.

Existing building stock: Plastered solid brick external wall – intermediate floor, timber beams Preliminary questions • Is there a water-resistant exterior plaster system? • Are there any cracks? Description of the renovation The existing building stock will be thermally renovated through an interior insulation on the external wall. • The ceiling and floor construction remains in place in accordance with the existing building stock. An uninterrupted connection of the airtight layers is not possible. • Therefore, a comfort ventilation system operated at negative pressure is required in any case (see page 69). • By leaving the connection in the ceiling area, the heat insulation in this area is reduced; as a result, the temperature on the beam ends rises in comparison to a continuous insulation. • For planning purposes, a dynamic moisture simulation, conducted by an experienced construction physicist who takes the existing framework conditions into account, is required in any case!

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Building tasks D29 | Solid brick external wall with interior insulation through facing layer – intermediate floor, timber beams

Suitability • If penetrating moisture from outside (driving rain) can be surely ruled out (vapor-permeable hydrophobization, closing of all cracks) (see page 48) • If exterior renovation is not possible (listed building, etc.) • Not suitable for renovating one apartment at a time Construction process

• Close cracks in the interior plaster; make an airtight connection at the foot level of the parquet floor with a vapor-permeable sheet. Even it out, if necessary. • Fully bond, plaster or fill the capillary-conductive panels. Insert expanding foam compression tape or soft insulation strips in the base area and bond them airtight onto the parquet floor. • Make an airtight and dampproof connection of the vapor barrier to the timber beams, e. g. bitumen slurry

• Repair exterior plaster, apply a vapor-permeable, water-resistant coating

Existing building stock: Plastered solid brick external wall – intermediate floor, timber beams Preliminary questions • Is there a water-resistant plaster system on the outside? • Are there any cracks? • Are the external walls “dry?” Description of the renovation The existing building stock will be thermally renovated through an interior insulation on the external wall. • Penetrating moisture from outside must be surely ruled out. • The ceiling is opened in the edge area, the thermal insulation is inserted; the vapor barrier is connected in an airtight manner onto the timber beams. • A comfort ventilation system operated at negative pressure is advantageous. No moisture recovery will be carried out (see page 69). • Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). For planning purposes it is strongly recommended to consult an experienced construction physicist!

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Buildings erected up to 1918

D30 | External wall with capillary-conductive interior insulation – top story ceiling with loose fill insulation

Suitability

• Repair exterior plaster, apply a vapor-permeable, water-resistant coating

• For accessible attics • If penetrating moisture from outside (driving rain) can be surely ruled out (vapor-permeable hydrophobization, closing of all cracks) (see page 48) • Not suitable for renovating one apartment at a time

• Close cracks in the interior plaster; even out, if necessary. • Fully bond, plaster or fill the capillary-conductive panels. Insert expanding foam compression tape or soft insulation strips in the base area and bond them airtight onto the parquet floor. Discussion

Construction process • Fill, plaster the jamb wall, lay the vapor barrier, repair the existing plaster, connect it with the vapor barrier in the roof area

If structurally required, the perlite insulation can also be directly laid on the solid logs.

• Insert and compress perlite fill; lay the pore sealing panel on top, connect it in a windproof manner with the jamb wall plaster

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Is the roofing waterproof? • Use of the attic: Storage space, to dry laundry, unused? Description of the renovation • The capillary-conductive insulation panels are fully bonded onto the internal wall. • The top story ceiling is insulated with a perlite fill; a load distribution plate also makes the renovated attic accessible. • The newly laid vapor barrier on the ceiling is the airtight layer; this is bonded onto the filled jamb wall. Vertically, the new interior plaster is the airtight layer, which is connected in an airtight manner to the ceiling plaster. An uninterrupted connection of the airtight layers is not possible. • As a result of the insulation, the temperatures in the attic will be significantly lowered in the winter half-year. This is to be taken into account in the future utilization and ventilation of the attic (execution of ventilation openings, e.g., ventilation tiles, etc.). For planning purposes it is strongly recommended to consult an experienced construction physicist!

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Building tasks D31 | External wall with interior insulation, capillary-conductive – loft conversion with rafter doubling

Suitability • If penetrating moisture from outside (driving rain) can be surely ruled out (vapor-permeable hydrophobization, closing of all cracks) • Suitable for renovating one apartment at a time Construction process

• Close cracks in the interior plaster; make an airtight connection at the foot level of the parquet floor with a vapor-permeable sheet. Even it out, if necessary. • Fully bond, plaster or fill the capillary-conductive panels. Insert expanding foam compression tape or soft insulation strips in the base area and bond them airtight onto the parquet floor.

• Repair exterior plaster, apply a vapor-permeable, water-resistant coating

Existing building stock: Plastered solid brick external wall – solid log floor – tiled roof Preliminary questions • Are the rafters still statically usable? Description of the renovation • The rafters are reused, doubled up and insulated with fiber insulation. • The solid log floor, formerly the top story ceiling, is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The airtight layer is the newly laid vapor barrier in the roof, which is connected in an airtight manner across the plastered jamb wall to the existing exterior plaster. A continuous sealed layer is not possible in the support area of the rafters. • Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). A comfort ventilation system operated at negative pressure is strongly recommended.

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Buildings erected up to 1918

Details Roof: Internal wall – top story ceiling D32 | Solid brick load-bearing internal wall/plastered chimney – solid log floor, apartment separation floor

Suitability

Discussion

• I f solid log floor is still statically usable Construction process • Repair existing plaster on the chimney/internal wall, apply composite concrete, lay the bituminous vapor barrier/temporary seal and seal it onto the plaster

A thermal insulation of the chimney wall is thermally interesting for chimneys that are no longer active; however, the effective thermal storage mass of the chimney walls is strongly reduced as a result. A sensible decision is only possible in individual cases.

• Close no longer active chimneys on the top in order to avoid heat dissipation through convection

Existing building stock: Plastered solid brick internal wall – solid log floor Preliminary questions • Are chimneys still active? Description of the renovation • The solid log floor, formerly the top story ceiling, is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The airtight layer is comprised of the temporary seal and the plaster of the internal wall/chimney. Although it concerns internal building components, an airtight connection of both levels makes sense because of the acoustic insulation protection and for hygienic reasons.

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Building tasks D33 | Solid brick load-bearing internal wall, plastered – solid log floor, top story ceiling

Suitability

Discussion

• If solid log floor is still structurally usable Construction process • Repair existing plaster on the chimney/internal wall • Clean existing ceiling, lay vapor barrier and connect it airtight onto the plaster of the internal wall

On account of the chimney wall, a continuous airtight layer is not possible. A thermal insulation of the chimney wall is thermally interesting for chimneys that are no longer active; however, the effective thermal storage mass of the chimney walls is strongly reduced as a result. A sensible decision is only possible in individual cases.

• Close no longer active chimneys on the top in order to avoid heat dissipation through convection

Existing building stock: Solid brick load-bearing internal wall/chimney – solid log floor, top story ceiling Preliminary questions • Are chimneys still active? Description of the renovation • The solid log floor is executed with an accessible perlite thermal insulation under a load distribution plate. • The thermal bridge effect of the load-bearing wall can be reduced with perimeter insulation. • The vapor barrier on the existing ceiling, which is connected in an airtight and vaporproof manner onto the plaster of the internal wall/chimney, constitutes the airtight layer. • Mineral perimeter insulation

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Buildings erected up to 1918

Details Window: External wall – window D34 | Solid brick external wall with insulation between timber construction – passive house wood-aluminum window

Suitability • If historic building preservation reasons do not speak against it Construction process • The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface.

bond the existing exterior plaster and interior plaster to make them airtight. • The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over.

• Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These

Existing building stock: Plastered solid brick external wall – double casement window Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description of the renovation The existing stock will be thermally renovated by a timber construction with wooden universal columns, blown out with cellulose. • The timber construction will be mounted on site and closed on the outside with the wood fiberboard. • The windows will be replaced by wood-aluminum passive house windows set into the insulation level. • The existing exterior plaster, which is connected airtight onto the interior plaster, is the continuous airtight layer. The sash seal of the window is connected to the leveling screed/plaster.

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Building tasks D35 | Solid brick external wall with ETICS, tapered – passive house wood-aluminum window

Suitability • If historic building preservation reasons do not speak against it Construction process • The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface. • Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These bond the existing exterior plaster and interior plaster airtight.

• The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over. Discussion Shortened aluminum shells and thicker added insulation lower the thermal bridge loss.

Existing building stock: Plastered solid brick external wall – double casement window Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description of the renovation The external wall will be thermally renovated by an external thermal insulation composite system. • The windows will be replaced by wood-aluminum passive house windows set into the insulation level. • The continuous airtight layer is the existing exterior plaster. This is connected airtight with the interior plaster. The sash seal of the window is connected to the leveling screed/plaster. • By tapering the external thermal insulation composite system in the reveal, the degree of insolation, the view and the natural lighting can be increased.

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Buildings erected up to 1918

D36 | Solid brick external wall with ETICS – double casement window with double thermal insulation glazing, inside

Suitability • If the preservation of the original window is required • If vapor release or rear ventilation of the outer casement is possible

impermeability. Condensation can temporarily appear on the inner side of the outer casement. An icing (“frosting”) also appears when the vapor release/rear ventilation is professionally executed.

Construction process • The airtight layer is the existing exterior plaster; close the cracks. • Drill vapor release openings (holes) on the outer casement above and below the casement. Pay particular attention to driving rain

Existing building stock: Plastered solid brick external wall – double casement window Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • Window frame and outer casement are preserved and are set into the insulation layer; the inner casement is replaced by an optimized two-paned WSG wood window. • In order to keep the same window dimensions as in the existing building stock, the removal of the reveal mortar is necessary. The three-layered wood composite panel is, in principle, airtight (joints bonded). The existing exterior plaster and the window frame inner casement are newly connected in an airtight manner. • The sash seal of the window is connected onto the leveling screed/plaster.

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Building tasks D37 | Solid brick external wall with ETICS – double casement window with triple thermal insulation glazing, outside

Suitability

Discussion

• If the windows are explicitly required to be flush-mounted on the outside • If no high effectiveness of the intermediate sun protection is required

The flush setting of the outer casement is problematic from a hygric standpoint, since a permanent connection against driving rain is only possible when carefully executed. It is better not to execute it on façades strongly exposed to driving rain.

Construction process • The airtight layer is the existing exterior plaster; close the cracks, fill the entire surface. • Permanently bond the external window frames with plaster connection profile with reinforcement lug

Existing building stock: Plastered solid brick external wall – double casement window Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • Window frame and outer casement are preserved; the inner casement is replaced by a passive house window. • In order to keep the same window dimensions as in the existing building stock, the removal of the reveal mortar is necessary. The three-layered wood composite panel is, in principle, airtight (joints bonded). The existing exterior plaster is connected airtight to this. • The sash seal of the window is connected in an airtight and vaporproof manner onto the threelayered wood composite panel.

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Buildings erected up to 1918

D38 | Solid brick wall with internal insulation – box-type window with internal triple-glazing

Suitability • If it is necessary to retain the original external window • If it is possible to release vapor from or rear-ventilate the external leaf

driving rain. Condensation can temporarily occur on the inside of the external leaf. Icing (“frost patterns”) also occurs in the event of the correct execution of the vapor release/rear ventilation

Construction process • The airtight layer is the vapor barrier • Holes to release vapor are to be created above and below the external leaf. Extra care is to be taken to ensure imperviousness to

Existing building stock: Solid brick external wall, plastered – box-type window Preliminary questions • Existing rabbet on external wall? • Position of the window in the reveal? Description of the renovation The external wall is thermally refurbished using internal insulation with a facing panel (see page 48). • The window frame and external leaf are retained, the filler block is extended internally and the internal leaf is replaced with an optimized triple-glazed timber window fixed direct to the filler block • It is necessary to remove mortar from the reveal in order to retain the window dimensions of the existing building stock. • The sash seal of the window is connected to the vapor barrier of the facing panel.

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Building tasks D39 | Solid brick wall with internal insulation – box-type window with triple-glazing in the reveal

Suitability • If it is necessary to retain the original external window • If it is possible to release vapor from or rear-ventilate the external leaf

• Holes to release vapor are to be made above and below the external leaf. Extra care is to be taken to ensure imperviousness to driving rain. Condensation can temporarily occur on the inside of the external leaf. Icing (“frost patterns”) also occurs in the event of the correct execution of the vapor release/rear ventilation

• If a window sill is desired Construction process • Panels are to be fully glued/cemented, the airtight layer is the internal plaster

Existing building stock: Solid brick external wall, plastered – box-type window Preliminary questions • Existing rabbet on external wall? • Position of the window in the reveal? Description of the renovation The external wall is thermally refurbished using calcium silicate internal insulation (see page 48). • The window frame and external leaf are retained, the internal leaf is replaced with an optimized triple-glazed timber window fixed directly to the filler block. Purenit blocks or an additional layer of purenit are used where required for structural reasons. • It is necessary to remove mortar from the reveal and, on occasions, to remove bricks in order to retain the window dimensions of the existing building stock. This is generally not required in the case of reveals with a rabbet. • The sash seal of the window has a flow-proof plastered connection to the internal plaster

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Buildings erected up to 1918

Details Window: Roof – Window D40 | Roof extension with doubling of rafters – roof windows, optimized installation with Purenit-insulated sash and insulated frame, installed flush with roof cladding

1

1 Puren/Purenit®

Construction process

• Adapted solar protection systems are available

• T he airtight level is the vapor barrier in the roof construction which has a continuous airtight connection with the window frame (use prefabricated vapor barrier collar) • Removal of counter battens above and below the window in order to ensure the rear ventilation of the roof around the window • The wind-tight level is the vapor-permeable roofing membrane which is to be connected to the window frame (use prefabricated underfelt collar)

Discussion Passive house certified systems with 4 or 5 glass systems or an optimized system with insulating skirting are available and the possibility of using these is to be checked! Check if a heating source below the window is needed.

Existing building stock: Roof tiles, cold roof Preliminary questions • Are the rafters structurally suitable for the installation of roof windows? Note: The load-bearing structure is strengthened by the doubling of the rafters • Not applicable in the case of passive house certified roof window systems Description of the renovation The rafters are reused, doubled and insulated using fiber insulating material • The airtight level is the newly-laid vapor barrier in the roof which has vaporproof and flow-proof connections to the window frame

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Building tasks D41 | Roof extension with doubling of rafters – roof windows, installation with prefabricated insulated sash and wooden batten frame, standard installation

Construction process

• Adapted solar protection systems are available

• The airtight level is the vapor barrier in the roof construction which has an airtight connection to the window frames (use prefabricated vapor barrier collar) • Removal of counter battens above and below the window in order to ensure the rear ventilation of the roof around the window • The wind-tight level is the vapor-permeable roofing membrane which is to be connected to the window frame (use prefabricated underfelt collar)

Discussion Passive house certified systems with 4 or 5 glass systems or an optimized system with insulating skirting are available and the possibility of using these is to be checked! Check if a heating source below the window is needed.

Existing building stock: Roof tiles, cold roof Preliminary questions • Are the rafters structurally suitable for the installation of roof windows? Note: The load-bearing structure is strengthened by the doubling of the rafters • Not applicable in the case of passive house certified roof window systems Description of the renovation The rafters are reused, doubled and insulated with fiber insulation material • The airtight level is the newly laid vapor barrier in the roof which has vaporproof and flow-proof connections to the window frames

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Buildings erected from 1920 to 1950 Buildings erected from 1920 to 1950

Cap vault ceiling

The buildings described here were erected primarily during the interwar period (1918–1939).

Characterization of the existing building stock After the collapse of the old empires, the 1920s also brought a departure in the construction method. Reinforced concrete floors or precast floor slabs spread strongly, walls are also built as hollow bricks walls. Basement external walls and ceilings are increasingly constructed in reinforced concrete. Wall thicknesses are reduced, since the building authorities no longer exclusively demand minimum thicknesses based on experience, but require a structural certification.

Brick vault between steel beams.

Floor in contact with the ground See buildings erected up to 1918

Internal walls External walls and external walls in contact with the ground The construction methods of the walls are still very similar to those before 1918. Solid bricks continue to be the preferred building material for all types of walls. Hollow bricks and aerated concrete blocks are additionally used to save materials and for heat insulation, especially in buildings with low structural requirements. Unplastered walls are not only executed on the outside for aesthetic reasons. These are partially executed on the outside as cavity external walls with a clinker shell, whereby the air space is rear-ventilated or is executed only with a standing air layer. The shells are connected with header bricks or anchors. Single wall construction with directly bricked clinker facings are especially found in commercial buildings.

See buildings erected up to 1918

Intermediate floors In housing construction, timber beam ceilings continue to be the preferred ceiling construction. In commercial construction, steel beams and ribbed concrete floors are increasingly used in the upper stories. Sand-cement screeds are increasingly laid under the end flooring; anhydrite and magnesite screeds are also applied. Clay and lime screeds almost completely disappear. Timber beam ceiling

Lime mortar with a portion of cement is already used largely for bricking up. Interior plasters are still lime plasters for the most part.

Solid brick with facing, plastered on the interior The structure is similar to an intermediate floor. On the upper side, paving bricks are laid on the fill for fire prevention reasons.

Top story ceiling The top story ceiling leads most of the time into an unused roof space, which is executed as a “cold roof” and more or less rear-ventilated with outside air. In the interwar period, many ceilings are still executed as timber beam or solid log ceilings (particularly in housing construction), but steel beams and reinforced concrete slabs increasingly come into use as well (see buildings of the 1950s).

Decorative elements are respectively bricked into the wall.

Basement floors, basement external walls, basement internal walls For moisture protection reasons, basement ceilings were solidly built in most cases. In addition to the cap vault ceilings already increasingly utilized before 1918, steel beams, concrete slabs and aerated concrete blocks are now being employed as well. In most cases, a 3to 5-cm-thick layer of topping concrete is also poured. Reinforced concrete slabs are increasingly used.

Detail of Passive Houses: Renovation

The structure is similar to an intermediate floor. On the upper side, paving bricks are laid on the fill for fire prevention reasons.

Roof Similar to those before 1918, roofs of buildings from the interwar period were almost completely built as carpentry constructions. Most of the time, different forms of roof tiles, which are attached to the roof battens, were used for the roof covering. In addition, sheet

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Building tasks metal roofs were also constructed, as well as, particularly in rural regions, roof coverings with wood shingles, straw or stone plates. Tiled roof

Defects/Types of damage The following types of damage are typical for buildings of the interwar period: • Moisture and salt damage in rising masonry • Timber beams of the intermediate floors or the top story ceiling are rotted • Condensation damage on the steel windows • Façade: Chipping plaster or decorative plasterwork, soiled façade

Renovation tasks Rafter thicknesses range mostly from 12 cm to 18 cm.

Windows Depending on the region, windows are executed as double casement windows or as windows with single casements. The execution is very similar to that prior to 1918. As far as form is concerned, the windows are increasingly set horizontally rather than vertically. Since the effort required to set them is significantly lower, wood composite windows are increasingly used, especially from 1950 onwards. In addition, steel windows, mostly single-glazed, but sometimes double-glazed for heat insulation reasons, increasingly find use particularly in commercial construction. Steel framed windows

• Exterior insulation, possibly with reconstruction techniques for façade ornamentation, if existent • Interior insulation with particular attention to joints, especially with unplastered façades (mitigation of thermal bridges/mold problem) • Inclusion of the stairwell (mezzanine problem) • Insulation of the top story ceiling, accessible, non-accessible, joints of the eaves • Possible loft conversion, new terraces • Window renovation, partially with special double casement windows, junctions; preserve the visual effect of the steel windows, with improved thermal and acoustic insulation • Insulation of the basement ceiling slab, minimization of thermal bridges across external walls and internal walls or stairwells • Construction of new balconies or enlargement of existing ones • Moisture protection against driving rain, rising dampness • Improvement of airtightness • Improvement of acoustic insulation to the outside (windows and window junctions) • Improvement of acoustic insulation between living units (walls, ceilings) • Improvement of fire protection between the living units • Optimized room ventilation

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Buildings erected from 1920 to 1950 Details Base: External wall – basement ceiling slab D42 | Solid brick external wall with interior insulation – basement ceiling slab, insulated on the upper side with fill

Suitability • If exposure to rising damp and efflorescence is low (see page 26) • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) (see page 48) • If external renovation is not possible (listed building, etc.) • If evidence through hygrothermal simulation exists Construction process

• If only existent in parts, extend the existing interior plaster as an airtight layer up to the ceiling slab • Insert and compact perlite fill, add wood fiberboard • Lay the vapor barrier; make an airtight connection with the interior plaster • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

• Remove existing floor construction and fill

Existing building stock: Solid brick external wall – basement with vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description The existing building stock will be thermally renovated through an interior insulation on the external wall, as well as on the basement ceiling area. • The thermal bridge-free connection of the vertical insulation layer with the horizontal one is an advantage. • Through the interior insulation, the temperatures of the support structure will be significantly lowered in the winter half-year. The insulation thicknesses are to be adapted according to the external and internal climate. • Through the thermal insulation of the basement ceiling slab, the temperature in the basement is lowered and, without accompanying measures, the relative humidity in the basement is increased.

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Building tasks D43 | Solid brick external wall with façade insulation panel and rainscreen cladding – insulated external wall in contact with the ground – uninsulated basement ceiling slab

Suitability • If exposure to rising damp and efflorescence is low (see page 26)

• Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone)

Construction process • Excavation depth depending on the structural possibilities • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the vertical seal.

Existing building stock: Solid brick external wall – basement with vaulted ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description The existing building stock will be thermally renovated by means of an horizontal perimeter insulation. The basement ceiling slab remains uninsulated; the external walls of the basement are insulated. • The external wall will be insulated with a glass wool façade insulation panel. The substructure of the façade is a stainless steel rod system suitable for a passive house. • The temperature of the basement room rises in the winter. This results in a lower relative humidity when the moisture sources remain constant, meaning advantages for storage. The temperature will also be lower in the summer, so a combination with intelligent basement ventilation makes sense (see page 26). • If the masonry is penetrated with moisture through surface water, the absorption can be stopped by applying the vertical seal and draining the masonry.

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Buildings erected from 1920 to 1950 Details Parapet: External wall – roof, unheated D44 | Solid brick external wall with façade insulation panel and rainscreen cladding – roof with rafter doubling – top floor with fill insulation

Suitability • For façades that can be externally insulated Construction process • Plaster the jamb wall with a base coat, apply composite concrete, lay bituminous vapor barrier/temporary seal, repair the existing exterior plaster, seal it airtight with an airtight foil onto the plaster base coat of the internal jamb wall

Existing building stock: Solid brick external wall – timber beam ceiling – tiled roof Preliminary questions • Are the rafters still statically usable? Description • The external wall will be insulated with a glass wool façade insulation panel. The substructure of the façade is a stainless steel rod system suitable for a passive house. • The rafters are reused, doubled up and insulated with fiber insulation. • The timber beam floor, formerly the top story ceiling, is constructed with composite concrete in order to replace the timber roof structure and to reach an acceptable impact sound protection. • The airtight layer is the newly laid vapor barrier in the roof, which is connected with an airtight seal across the plastered jamb wall to the existing exterior plaster. A contionuons airtight layer is not possible only in the rafter bearing area.

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Building tasks Details Window: External wall – window D45 | Solid brick external wall with façade insulation panel and rainscreen cladding – passive house window, insulatable

Suitability • If historic building preservation reasons do not speak against it Construction process • The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface. • Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These bond the existing exterior plaster and interior plaster airtight.

• The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over. Discussion • Shortened aluminum shells and thicker added insulation lower the thermal bridge loss.

Existing building stock: Solid brick external wall – steel framed window Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description • The external wall will be thermally renovated by means of a rainscreen cladding. • The windows will be replaced by wood-aluminum passive house windows set into the insulation level. • The existing exterior plaster, which is connected airtight onto the interior plaster, is the continuous airtight layer. The sash seal of the window is connected to the leveling screed/plaster.

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Buildings of the 1950s and 1960s Buildings of the 1950s and 1960s This period begins after the end of the Second World War and lasts until the end of the 1960s.

Characterization of the existing building stock The immediate postwar period in Central Europe was characterized by a shortage of material. Building materials were frequently “recycled” from structures destroyed in the war. Basements were mostly made of concrete; horizontal and vertical seals were often laid; as of the 1960s, seals in accordance with new standards were required. Load-bearing walls continued to be executed as brick masonry, however with hollow bricks, which were sometimes made of concrete blocks added with, for instance, crushed brick. The intermediate floors made of timber were finally replaced by solid ceilings. In-situ concrete floors started making their triumphal march in the 1960s. Prior to that, various types of suspended and prefabricated ceilings dominated. Small balconies are typical for the 1950s, larger and more intricate ones for the 1960s. The façades are smooth, without any ornamentation. Roof constructions are similar to those of the interwar period; coverings, however, increasingly consist of concrete and fiber cement roof tiles.

Basement ceiling slab (basement ceiling) Basement ceilings are almost exclusively realized as concrete slabs. In addition to the increasingly utilized “level” reinforced concrete slabs, ribbed concrete decks were mostly used in large volume residential construction, while suspended ceilings are usual in small volume buildings. Steel beams are also in use. Ribbed concrete deck

The rib forms can also be conical. In the basement area there is no suspended ceiling for the most part. Concrete block ceiling

External walls and walls in contact with the ground Solid brick walls are now only seldom built, replaced by clay blocks or cement-bonded blocks. Due to the high amount of bricks from destroyed residential buildings, concrete blocks with crushed brick aggregate are frequently used in construction. In addition, various aerated concrete blocks are increasingly utilized (“Ytong” aerated concrete, “Durisol” cement-bonded wood fiber blocks, etc.). Especially in school and commercial buildings, reinforced concrete frame constructions are increasingly realized as of 1960. They are filled in with wall blocks or with prefabricated concrete components. Particularly in Northern Germany, cavity wall construction is frequently carried out. Most of the time, the up to 8-cm-thick air layer is rearventilated to the outside.

Suspended ceiling bricks can be concrete blocks, aerated concrete blocks or, in single-family houses, also clay blocks. Reinforced concrete slab

In the area in contact with the ground, concrete walls are increasingly built; in single-family homes, however, walls are still often bricked up.

Crushed brick masonry

The thickness of the concrete slabs differs depending on the span width. Material was strongly saved because of the material shortage.

Floor in contact with the ground A basement was usual and in many cases the basement was used as a living space, party room, etc. A concrete slab of at least 10 cm thickness, which was poured onto a hardcore base, was standard. Bituminous sealing was increasingly used, although the standardization in Germany and Austria definitely stipulated this only for special cases.

Internal walls The format size of the bricks differs in the individual countries. Reinforced concrete wall

Load-bearing internal walls are constructed similar to the external walls. Masonry as well as reinforced concrete walls were used. Crushed brick masonry

Unreinforced concrete walls are mostly used in the basement.

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Building Functions Intermediate floors

Wood composite windows

In contrast to the prewar era, intermediate floors are almost consistently constructed in a solid manner. A series of special ceiling types is in use, whereby the (flat) reinforced concrete slab slowly finds more prevalence, particularly in multi-story housing construction. Top story ceiling The execution of the top story ceiling only differs little from the (bare) intermediate floors. In the late 1960s, tightly scrimped insulation layers (especially wood wool lightweight panels, but also mineral wool, cork and polystyrene) are used. Reinforced concrete slab

Windows are installed mostly with a window rabbet. Depending on the external wall, various special blocks are commonly used to construct the window reveal and lintel. The lintel area is mostly built with reinforced concrete lintels that are cast directly with the ceiling or with special blocks that are unreinforced and cast with concrete.

Roof In the post-war period as well, most of the roofs are constructed as pitched roofs. Through the use of flat pan tiles, instead of the earlier common plain tile roof covering, lower roof pitches, which are quite typical for buildings of the 1950s and especially the 1960s, can be constructed. Particularly in multistory buildings, jamb walls are not built. The top solid floor or the prefabricated concrete components built on top of it serve as the bearing for the timber roof construction. In addition to pitched roofs, flat roofs are increasingly implemented for the first time, and most of them feature bituminous sealing. Insulation layers are sometimes inserted under these, mostly in very low thicknesses up to 5 cm (primarily wood wool lightweight panels). Tiled cold roof

Defects/Types of damage The following types of damage are typical for buildings of the 1950s and 1960s: • Moisture damage on balconies and loggias and bordering building components occurs because the overlap of the reinforcement is not properly covered. • Low acoustic insulation • Moisture damage on external window sills • Moisture damage on flat roofs, missing vapor pressure equalization, mold damage inside on the building corners • Façade: Chipping plaster Because of the reinforced concrete construction of the basement, rising damp is (despite often missing seals) no longer a problem for the most part.

Renovation tasks • External insulation is unproblematic because there is no ornamentation. • Renovation or cutting off of the balconies/loggias, if structurally possible and newer and lower balconies protrude or at least halfprotrude • Interior insulation with particular attention to corner joints (mitigation of thermal bridges/mold problem) • Inclusion of the stairwell (problem of mezzanines in stairwells which partially border on heated floors, partially on unheated floors) • Insulation of the top story ceiling, accessible, non-accessible, connections to the eaves (projecting reinforced concrete slabs) • Possible loft conversion, new terraces Besides fired roof tiles, bituminous seals, as well as concrete and fiber cement tiles, are used as covering.

Windows Wood composite windows increasingly come into use, since their installation involves significantly less effort than for double casement windows.

• Window renovation, replacement • Insulation of the basement ceiling slab, minimization of thermal bridges across external walls and internal walls, stairwell • Improvement of airtightness • Improvement of acoustic insulation to the outside (windows and window junctions) • Improvement of acoustic insulation between living units (walls, ceilings) • Improvement of fire protection between the living units • Optimized room ventilation

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Buildings of the 1950s and 1960s Details Base: External wall – basement ceiling slab D46 | Crushed brick masonry with ETICS – concrete hollow block ceiling, insulated on the lower side

Suitability • With low exposure to rising damp • If exposure to efflorescence is low • If drainage is required, the ground has to be dug up in any case. Construction process • E xcavation depending on the structural possibilities • Create a clean surface (plaster base coat) before applying the vertical seal

• Fully bond perimeter insulation panels to the basement wall, insert an expanding foam seal on the upper side, attach drip edge, plaster wall • Drainage requirements (see page 21) • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

• The exterior plaster of the basement wall is the airtight layer.

Existing building stock: Crushed brick masonry – concrete hollow block ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The basement ceiling slab will be insulated on the lower side, the basement walls will be insulated externally and internally (horizontal perimeter insulation). • The temperature of the basement room decreases in the winter. This results in a higher relative humidity when the moisture sources remain constant. Therefore, a combination with intelligent basement ventilation makes sense.

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Building tasks D47 | Crushed brick masonry with insulation between timber construction – ribbed concrete deck, insulated on the lower side

2 Suitability • If the external wall in contact with the ground is not suitable for applying the seal, create a clean surface (plaster base coat) before applying the vertical seal. • If drainage is required, the ground has to be dug up in any case. • Excavation depending on the structural possibilities Construction process • Seal the airtight layer (exterior plaster, fully filled if required) all the

way to the lower edge of the ceiling. This also provides a clean surface for applying the seal. Bituminous slurry is to be used in the seal area. • Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone) • Bond and mechanically secure the drip edge to the end of the timber construction (OSB panel) • Bond the ECB membrane on the lower end of the timber construction (OSB panel)

Existing building stock: Crushed brick masonry – ribbed concrete deck Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation • The external wall will be thermally renovated by insulation between the timber construction. • The basement ceiling slab will be insulated on the lower side; the basement walls will be insulated outside to the upper edge of the foundation. • The temperature of the basement room deceases in the winter on account of the ceiling insulation. This results in a higher relative humidity when the moisture sources remain constant. Therefore, a combination with intelligent basement ventilation makes sense.

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Buildings of the 1950s and 1960s D48 | Crushed brick masonry with ETICS – reinforced concrete basement ceiling slab, insulated on the lower side – basement window, renovated

Suitability • If the external wall in contact with the ground is not suitable for applying the seal, create a clean surface (plaster base coat) before applying the vertical seal. • If drainage is required, the ground has to be dug up in any case.

• The continuous airtight layer is the existing exterior plaster. This is connected airtight with the interior plaster. The sash seal of the window is connected to the leveling screed/plaster. • Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone) • Drainage requirements (see page 21)

Construction process • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the seal. Bituminous slurry is to be used in the seal area.

• Fully bond perimeter insulation panels to the basement wall, insert an expanding foam seal on the upper side, attach drip edge, plaster wall

Existing building stock: External wall of crushed brick masonry – reinforced concrete basement ceiling slab – basement window Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The basement ceiling slab will be insulated on the lower side, the basement walls will be insulated externally (horizontal perimeter insulation). • The windows will be replaced by wood-aluminum windows that are set in the insulation layer. If the distance between the upper edge of the ceiling and the upper frame of the window is very small, a frame doubling in the upper window area can be considered. • The temperature of the basement room decreases in the winter. This results in a higher relative humidity when the moisture sources remain constant. Therefore, a combination with intelligent basement ventilation makes sense.

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Building tasks Details base: Internal wall – basement ceiling slab D49 | Crushed brick masonry – reinforced concrete slab insulated on the lower side

Suitability

Discussion

• If exposure to rising damp and efflorescence is low • If the ground floor apartment can be vacated for the renovation

Particularly suitable for “dry” basements with moisture reserves if no high requirements are placed on the moisture behavior.

Construction process • Extend the existing interior plaster as the airtight layer to the structural slab • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

Existing building stock: Crushed brick masonry – reinforced concrete slab Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused Description of the renovation • The basement ceiling slab will be insulated on the lower side with glass wool. • The internal wall will be thermally renovated by an horizontal perimeter insulation. • The temperature of the basement room decreases in the winter. This results in a higher relative humidity when the moisture sources remain constant. Therefore, a combination with intelligent basement ventilation makes sense. • If the masonry is penetrated with moisture through surface water, the absorption can be stopped by applying the new vertical seal and draining the masonry.

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Buildings of the 1950s and 1960s Details intermediate stories: External wall – intermediate floor D50 | Crushed brick masonry with ETICS – top story ceiling, insulated on the upper side

2

Suitability • For façades without elaborate decorative plasterwork Construction process • The airtight layer is the existing exterior plaster: close the cracks; if necessary fill the entire surface. • Plaster on the inside should likewise be applied in an airtight manner up to the upper edge of the perimeter insulation.

Existing building stock: Crushed brick masonry – reinforced concrete slab with screed and flooring Preliminary questions • Is there a thermal bridge in the external wall ceiling area? Description of the renovation • The external wall will be thermally renovated by the external thermal insulation. • A vapor-permeable, but water-resistant plaster system will also decrease the amounts of water penetrating through driving rain. • The top story ceiling will be renovated with rigid insulation and a fire protection panel. • Perimeter insulation reduces the heat losses above the rising gable wall.

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Building tasks D51 | Crushed brick masonry with ETICS – top story ceiling, insulated on the upper side (eaves)

Suitability

Discussion

• For accessible attics Construction process • L ay vapor barrier, repair existing exterior plaster; bond it with the vapor barrier in the roof area

The construction of the eaves gutter is carried out to retain the proportions in the exterior area. If this is not required for design reasons, the existing construction can be replicated with an edge gutter. As a result, the external wall connection “slides” approx. 30 cm upwards.

• Lay EPS insulation and an accessible load distribution plate • Uncover the roof in the eaves area, double the rafters with fillets, lay the cladding and vapor-permeable roofing sheet, seal them in a windtight manner with the pore sealing panel and exterior plaster

Existing building stock: Crushed brick masonry – reinforced concrete slab Preliminary questions • Is the roofing waterproof? • Use of the attic: Storage space, to dry laundry, unused? Description of the renovation • The external wall will be thermally renovated by means of an external thermal insulation composite system. • The top story ceiling will be insulated with EPS insulation; a load distribution plate also makes the renovated attic accessible. • The airtight layer is the newly laid vapor barrier on the ceiling, which is connected with an airtight seal to the existing exterior plaster. • As a result of the insulation, the temperatures in the attic will be significantly lowered in the winter half-year. This is to be taken into account in the future utilization.

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Buildings of the 1950s and 1960s Details parapet: External wall – roof D52 | Gable wall made of crushed brick masonry with ETICS – tiled cold roof (verge)

Suitability • For ventilated attics Construction process • Reinforce the battens, if necessary

Existing building stock: Crushed brick masonry – tiled cold roof Preliminary questions • Is the roofing waterproof? • Use of the attic: Storage space, to dry laundry, unused? Description of the renovation • The external wall will be thermally renovated by means of an external thermal insulation composite system. • As a result of the insulation, the temperatures in the attic will be significantly lowered in the winter half-year. This is to be taken into account in the future utilization and ventilation of the attic.

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Building tasks Details window: External wall – window D53 | Crushed brick masonry with ETICS – insulatable passive house window frame

Suitability • If historic building preservation reasons do not speak against it Construction process • The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface. • Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These bond the existing exterior plaster and interior plaster airtight.

• The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over. Discussion Shortened aluminum shells and thicker added insulation lower the thermal bridge loss.

Existing building stock: Crushed brick masonry – wood composite windows Preliminary questions • What is the position of the window in the reveal? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The windows will be replaced by insulatable passive house windows in the insulation layer.

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Buildings of the 1950s and 1960s D54 | Crushed brick masonry with ETICS – insulatable passive house window frame and blind

Suitability • If historic building preservation reasons do not speak against it Construction process

• The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over.

• The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface. • Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These bond the existing exterior plaster and interior plaster airtight.

Existing building stock: Crushed brick masonry, wood composite windows Preliminary questions • What is the position of the window in the reveal? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The windows will be replaced by wood-aluminum passive house windows set into the insulation level. • The existing exterior plaster, which is connected airtight onto the interior plaster, is the continuous airtight layer. The sash seal of the window is connected to the leveling screed/plaster.

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Building tasks Buildings of the 1970s The late 1960s and the early 1970s are still defined by a boundless belief in the future. The Mideast Oil Crisis (1973) and the Report to the Club of Rome (1972) reveal the “limits to growth.” The construction method changes only slightly compared to the 1960s. Thermal insulation, however, improves through standardization.

The woodchip concrete thickness can vary; especially the external component, which meets the increased thermal protection requirements, is thicker. Reinforced concrete basement wall

Characterization of the existing building stock Basic construction does not differ significantly from the 1960s. In multistory housing construction the internal walls are increasingly utilized as load-bearing walls in order to attain larger building depths. Balconies are consistently replaced by loggias. The balustrades are partially used for greening purposes; in addition, prefabricated components are structurally integrated in many cases, too. Flat roofs are now usual for larger buildings and utility buildings, even if the sealing problems are not really solved yet. From 1973 on, the requirements for thermal insulation are substantially increased. This results in the usage of insulation materials in multi-story housing construction (inside, as well as increasingly on the outside and/ or sandwich construction). In single-family housing construction, porous bricks and aerated concrete with increased wall thicknesses are being used more and more. The first prefabricated houses made of lightweight construction materials are built.

In single-family house construction the walls are still made for the most part out of tamped concrete; in multistory construction the basement walls are reinforced. Clay block with clinker brick facing

Exposed concrete components turn out to be problematic, since the covering of the reinforcement is usually less than 2 cm. Reinforced concrete prevails as the material of choice for the construction of intermediate floors. Precast concrete skeleton construction is widespread in commercial construction. Windows particularly feature double-paned insulation glazing with aluminum spacers (sometimes triple-paned glazing is already being installed). Wood remains the preferred material for window frames. Highquality tropical timber is also frequently used. The treatment of lumber with hazardous wood preservatives (e.g., Lindane, PCP, etc.) is common.

The inner shell is dimensioned according to thermal insulation requirements. After 1973, thermal insulation is already attached onto the load-bearing brick. Clay block

External walls and walls in contact with the ground In large-volume housing construction, normal weight concrete walls with internal insulation or in sandwich construction (with exposed concrete on the outside) are increasingly used. In addition, woodchip concrete hollow block masonry experiences a high point. The (for the most part only slightly) insulating haunch layers are bonded with the structurally effective and mostly reinforced core concrete. Building with prefabricated components gains popularity. In single-family housing construction, porous bricks and lightweight concretes such as aerated concrete, pumice concrete and formed concrete are utilized more and more as wall thicknesses increase. Basement walls, protected against moisture penetration with bituminous seals, are built in reinforced concrete in multistory housing construction. Water resistant concrete structures are already being manufactured. Woodchip concrete masonry

Typical for single-family houses. The brick becomes increasingly porous as thermal insulation requirements rise and is laid in higher thicknesses.

Basement ceiling slab Basement ceiling slabs are increasingly executed as (flat) reinforced ceiling slabs. Thermal insulation that also possesses an impact sound absorption function (flanking transmissions) is executed mostly on the upper side. Suspended ceilings are still being executed especially in single-family house construction. Reinforced concrete slab with tile flooring

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Buildings of the 1970s With the tightening of thermal insulation requirements, insulation thicknesses increase in most Central and Northern European countries.

Brick element floor slab

Reinforced concrete slab with parquet flooring

Often no insulation was used in single-family house construction as well.

Top story ceiling Floor in contact with the ground The construction of a basement is usual. In many cases, the basement is upgraded as a living space, party room, etc. A concrete slab of at least 10 cm thickness, poured onto a hardcore base, is standard. Bituminous sealing is used as a standard.

Due to thermal insulation requirements, the reinforced concrete top story ceilings had to be additionally insulated. Wood wool lightweight panels were initially used, later primarily mineral wool and, if fire protection reasons permitted, expanded polystyrene.

Reinforced concrete slab Floor slab with strip foundation

Seals against rising soil moisture are often frequently laid on the weak concrete blinding slab. The concrete slabs are sometimes executed without seals, but with a higher cement portion if there is no high-quality usage of the basement.

Internal walls The load-bearing internal walls are constructed for the most part like the external walls. Although not new, multilayered lightweight walls made of gypsum plasterboards, gypsum fiberboards or gypsum planks are increasingly used.

Execution in flat roofs. Walkable surfaces (screed, gypsum fiberboards, EPV panels) were chosen with pitched roofs.

Roof Roofs are diversely executed: In multi-story housing construction flat roofs increasingly become prevalent, whereby warm roofs and inverted roofs are used more and more. In addition, sheet metal roofs that drain inwardly are widespread. Pitched roofs are still mainly built on single-family houses. Tiled roof over the cold roof

Woodchip concrete composite blocks

As opposed to older buildings, timber cladding was attached and a bituminous covering executed. The attic is ventilated outwards. Core concrete thickness according to structural requirements.

Tiled cold roof, plastered

Intermediate floors Reinforced ceiling slabs are almost exclusively used in multi-story housing construction. Suspended ceilings are also executed in single-family house construction. Reinforced concrete slab with parquet flooring

Executed for the converted attic, especially of single-family and row houses. The air space between the rafters is ventilated towards the outside (cold roof). The slab thicknesses vary depending on the span widths.

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Building tasks Flat roof

Renovation tasks • External insulation is unproblematic because there is no ornamentation; milling off existing synthetic resin plasters may be required. • Renovation or cutting off of the balconies/loggias, if structurally possible and newer and lower balconies protrude or at least halfprotrude • Flat roof renovation

The roof drains inwardly.

Windows Insulated glazing with aluminum spacers becomes prevalent. Double-paned glazing is common, but due to the large formats, triplepaned glazing is already being executed. Because of the larger window sizes, fixed glazing and terrace doors are frequently realized. Coniferous wood serves primarily as window frame material; tropical wood is also increasingly used. Stick system façades are increasingly used above all in commercial construction. Wooden windows treated with wood protection materials (Lindane, PCP), which are classified today as toxicologically extremely hazardous, are the standard. Wooden insulated glass windows

• Removal of the planters • Interior insulation with particular attention to the corner joints (mitigation of thermal bridges/mold problem) • Inclusion of the stairwell (problem of mezzanines in stairwells which partially border on heated floors, partially on unheated floors) • Insulation of the top story ceiling, accessible, non-accessible, connections to the eaves (projecting reinforced concrete slabs) • Possible loft conversion, new terraces • Window renovation, replacement of the glazing and/or, depending on the condition and material, the frame as well • Insulation of the basement ceiling slab, minimization of thermal bridges across external walls and internal walls, stairwell • Improvement of airtightness • Improvement of acoustic insulation to the outside (windows and window junctions) • Improvement of acoustic insulation between living units (walls, ceilings) • Improvement of fire protection between the living units • Optimized room ventilation

Sheet metal and stone plates are frequently used as outer window sills.

Defects/Types of damage The following types of damage are typical for buildings of the 1970s: • Moisture damage on balconies and loggias and bordering building components occurs because the overlap of the reinforcement is not properly covered. • Low acoustic insulation • Moisture damage on flat roofs, missing vapor pressure equalization, mold damage inside on the building corners • Façade: Chipping plaster • Exposed concrete: Moisture damage through spalling, damage on the reinforcement

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Buildings of the 1970s Details base: External wall – basement ceiling slab D55 | Exterior wall with ETICS – basement ceiling slab, insulated with ETICS on the lower side

Suitability • If no high-quality usage of the basement is expected Construction process • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the seal.

• Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. • Drainage requirements (see page 21) • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

• Bond the insulation panels on the basement ceiling and, depending on the subsurface, additionally dowel them

Discussion

• Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone)

As an alternative to bitumen cloth, the top layer can be completely bonded with perimeter insulation panels and the lowest layer with ETICS panels; carefully close vertical panel joints

• Tightly seal (e.g., torch down) the polymer damp-proof membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge

Existing building stock: External wall with woodchip concrete composite blocks – reinforced concrete slab Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description • The external wall will be thermally renovated by an external thermal insulation composite system executed on the basement wall and external wall. • The basement ceiling slab will likewise be insulated on the lower side with an external thermal insulation composite system. • The temperature of the basement room decreases in the winter on account of the insulation. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks D56 | Woodchip concrete wall with insulation between the prefabricated timber construction, rear-ventilated – reinforced concrete slab, insulated on the lower side

Suitability • For a basement without high-quality use Construction process • S eal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the seal. • Bond the insulation panels on the basement ceiling and, depending on the subsurface, additionally dowel them • Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone) • Bond and mechanically secure the drip edge to the end of the timber construction

• Bond the ECB membrane on the lower end of the timber construction (OSB panel) • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69) Discussion If a sealed surface (e.g., sidewalk) on the outside area connects directly (without a drainage layer) to the external wall, form the surface with an incline going away from the house

Existing building stock: Woodchip concrete composite block wall – reinforced concrete basement ceiling slab Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description • The external wall will be thermally renovated by a prefabricated timber construction which is blown out with cellulose insulation on site. • The basement ceiling slab will likewise be thermally renovated on the lower side with an external thermal insulation composite system. • XPS thermal insulation is envisaged in the base area and the area in contact with the ground. • The temperature of the basement room decreases in the winter in comparison to the existing building stock. This results in a higher relative humidity when the moisture sources remain constant (see page 26).

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Buildings of the 1970s D57 | Woodcip concrete composite block wall with ETICS – basement ceiling slab insulation, with vacuum insulation on the upper side

Suitability • For a basement without high-quality use Construction process • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the seal. • Fully bond the vacuum insulating panels onto the PE soft foam panel. In case it is not level, apply a leveling layer on the structural slab. • Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone) • Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation

of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. • Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69) Discussion As an alternative to bitumen cloth, the top layer can be completely bonded with perimeter insulation panels and the lowest layer with ETICS panels; carefully close vertical panel joints.

Existing building stock: Woodchip concrete composite block wall – reinforced concrete basement ceiling slab Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description • The external wall will be thermally renovated by an external thermal insulation composite system executed on the basement and external walls. • The basement ceiling slab will be thermally renovated on the upper side with vacuum insulating panels to preserve the original height. • The temperature of the basement room is lower in the winter in comparison to the existing building stock. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks Details base: Internal wall – basement ceiling slab D58 | Woodchip concrete internal wall – reinforced concrete slab, insulated on the lower side

Suitability • For a basement without high-quality use Construction process • T he airtight layer is the reinforced concrete slab, which is airtight in itself. • Bond the insulation panels on the basement ceiling and, depending on the subsurface, additionally dowel them

• Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69) Discussion Perimeter insulation is advisable if the basement temperature can get very low.

Existing building stock: Woodchip concrete wall – reinforced concrete slab Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description of the renovation • The basement ceiling slab will be insulated on the lower side with a thermal insulation composite system. To reduce thermal bridge losses and to increase the minimum temperature on the ground floor, perimeter insulation will be applied. • The temperature of the basement room is lower in the winter in comparison to the existing building stock. This results in a higher relative humidity when the moisture sources remain constant.

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Buildings of the 1970s D59 | Woodchip concrete internal wall – basement ceiling slab, with vacuum insulation on the upper side, cement screed

Suitability • For a basement without high-quality use Construction process

• Consider the use of an intelligent ventilation system, particularly with high requirements on the storage quality of the basement (see page 26 and 69)

• The airtight layer is the reinforced concrete slab, which is airtight in itself. • Fully bond the vacuum insulating panels onto the PE soft foam panel. In case it is not level, apply a leveling layer on the structural slab.

Existing building stock: Woodchip concrete composite block wall – reinforced concrete slab Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description of the renovation • The basement ceiling slab will be thermally renovated on the upper side with vacuum insulating panels to preserve the original height. • The temperature of the basement room is lower in the winter in comparison to the existing building stock. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks Details base: External wall – floor in contact with the ground D60 | Woodchip concrete wall with ETICS – floor with vacuum insulation

Suitability • For spaces in contact with the ground with the same high floor structure after renovation Construction process • Excavation depth depending on the structural possibilities • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the seal. • Fully bond the vacuum insulating panels onto the PE soft foam panel. In case it is not level, apply a leveling layer on the structural slab. • Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone)

• Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge. • Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. • Drainage requirements (see page 21) Discussion As an alternative to bitumen cloth, the top layer can be completely bonded with perimeter insulation panels and the lowest layer with thermal insulation composite system panels; carefully close vertical panel joints.

Existing building stock: Woodchip concrete wall – floor with strip foundation, bonded screed Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description of the renovation • The outer wall will be thermally renovated by an external thermal insulation composite system executed on the basement and external walls. • The basement ceiling slab will be thermally renovated on the upper side with vacuum insulating panels to preserve the original height. • The existing exterior plaster, which is sealed airtight with the reinforced concrete floor slab, constitutes the vertical airtight layer.

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Buildings of the 1970s Details parapet: External wall – roof, unheated D61 | Porous clay block external wall with ETICS – tiled roof with over-rafter insulation and canopy, eaves

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, mount the timber cladding. The vapor barrier is bonded airtight with the existing exterior plaster of the wall.

• Attach the assembly component in the eaves area; mount the fillets, like in the existing building stock, in the edge area for the large-dimensioned canopy; add over-rafter insulation, wood fiberboard and wind barrier. • Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof will be opened from the outside, the layers between the rafters insulated. Insulation will be placed above the over-rafters. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Building tasks D62 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, eaves

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, set the prefabricated parts, which are open upwards, for mounting. Close with wood fiber sub-roof panel and the vaporpermeable roofing sheet.

• The top rafter of the box truss will be led outwards for the canopy (also suitable for strongly protruding canopies) • The vapor barrier is bonded airtight with the existing exterior plaster of the wall. • Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels.

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof is opened from the outside; the level between the rafters is insulated; a partially prefabricated, insulated timber construction is mounted and closed on site. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Buildings of the 1970s D63 | Porous clay block external wall with insulation between prefabricated timber construction – tiled roof with prefabricated timber components, eaves

Suitability

• Build the canopy with suitably sized counter battens

• For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, install the timber prefabricated components for the roof.

• Bond the vapor barrier airtight with the existing exterior plaster of the wall • Install the prefabricated wall components, fill with cellulose flakes

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated with a prefabricated timber construction, which is blown out with cellulose on site. • The roof is opened from the outside; the level between the rafters is insulated; a prefabricated, insulated timber construction is mounted. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Building tasks D64 | Porous clay block external wall with ETICS – tiled roof with over-rafter insulation and canopy, verge

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, mount the timber cladding. The vapor barrier is bonded airtight with the existing exterior plaster of the wall.

• Attach the assembly component in the eaves area; mount the fillets, like in the existing building stock, in the edge area for the large-dimensioned canopy; add over-rafter insulation, wood fiberboard and wind barrier. • Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof is opened from the outside; the level between the rafters is insulated; warm roof construction is placed above it. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Buildings of the 1970s D65 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, verge, variant 1

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, place the prefabricated parts, which are open upwards, for mounting. Close with wood fiber sub-roof panel and the vaporpermeable roofing sheet.

• The top rafter of the box truss will be led outwards for the canopy (also suitable for strongly protruding canopies). • Bond the vapor barrier airtight with the existing exterior plaster of the wall • Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof is opened from the outside; the level between the rafters is insulated; a partially prefabricated, insulated timber construction is mounted and closed on site. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Building tasks D66 | Porous clay block external wall with ETICS – tiled roof with partially prefabricated timber construction, verge, variant 2

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, place the prefabricated parts, which are open upwards, for mounting. Close with wood fiber sub-roof panel and the vaporpermeable roofing sheet.

• The top rafter of the box truss will be led outwards for the canopy (also suitable for strongly protruding canopies). • Bond the vapor barrier airtight with the existing exterior plaster of the wall • Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels.

Existing building stock: Porous clay block external wall – tiled roof, plastered on the inner side on a plaster baseboard Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof is opened from the outside; the level between the rafters is insulated; a partially prefabricated, insulated timber construction is mounted and closed on site. • The canopy is built with a multi-layered solid wood panel. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Buildings of the 1970s Details parapet: External wall – heated roof D67 | Woodchip concrete composite block wall with ETICS – reinforced concrete roof as a terrace with wooden grating

Suitability • If the structural slab is structurally suitable Construction process • Remove roof structure, remove the parapet up to the level of the top edge of the structural slab • Clean the exterior plaster, repair missing parts. The exterior plaster constitutes the airtight layer. Connect it to the concrete grating.

• Fasten the railing onto pressure-resistant thermal decoupling made of Purenit® • Fully bond the insulation panels in the concrete grating area in order to safely exclude an upward vapor release in the separating layer between the existing plaster and the insulation panels • Lay perforated sheet metal in the outermost area under the seal in order to safely avoid standing water in the area where the EPS panels connect to the wooden grating.

• Lay bituminous vapor barrier/temporary seal; if required, apply the leveling layer beforehand. Make an airtight connection to the exterior plaster.

Existing building stock: Woodchip concrete composite block wall – flat sheet metal roof on gang nail truss Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The parapet and the timber construction of the roof will be removed. • The external wall will be thermally renovated by an external thermal insulation composite system. • The ceiling will be renovated with a non-ventilated flat roof system. The railing will be executed as far as possible on the outside in order to keep the terrace surface as large as possible. • The airtight layer is the existing exterior plaster; the bituminous vapor barrier on the structural slab will be connected in an airtight manner to the exterior plaster.

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Building tasks D68 | Woodchip-concrete composite block wall with ETICS – flat roof insulation under vapor pressure-equalized metal roof sheeting

Suitability

• Lay the vapor-permeable roofing sheet, weld the joints

• If the timber construction of the roof is further usable • If the reinforced concrete slab is sealed in an airtight manner Construction process • Remove metal roof sheeting, open the timber cladding in parts • Clean the exterior plaster, repair the missing parts. The exterior plaster constitutes the airtight vertical layer. Apply plaster base coat above the parapet to the top edge of the timber cladding. • Keep existing thermal insulation, if possible. Insulate the interstice with fiber insulation material, close the openings again. Fasten the timber construction around the attic and insulate it with rock wool.

• Lay the counter battens, nail on the timber cladding, attach the roof seal and metal roof sheeting • Fully bond the insulation panels in the parapet area in order to safely rule out a upward vapor release in the separating layer of the existing plaster and the insulation panels Discussion As an alternative, remove the parapet and construct a lightweight parapet.

Existing building stock: Woodchip concrete composite block wall – metal roof sheeting on gang nail truss Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The timber construction of the roof will be preserved, partially opened and insulated. The metal roof sheeting will be replaced by a vapor pressure-equalized/rear-ventilated metal roof sheeting. • The airtight layer is the existing exterior plaster; the bituminous vapor barrier on the structural slab will be connected in an airtight manner to the exterior plaster.

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Buildings of the 1970s D69 | Woodchip concrete composite block wall, insulated with cellulose between the timber construction, rear-ventilated – flat roof with duo roof insulation

Suitability • If the structural slab is structurally suitable Construction process • Clean exterior plaster, repair missing parts. The exterior plaster constitutes the airtight layer. Seal it airtight on the concrete grating with sealing tape.

• Fully bond the insulation panels in the parapet/concrete grating area in order to safely rule out an upward vapor release in the separating layer of the existing plaster and the insulation panels Discussion As an alternative, the roof can also be renovated with a prefabricated timber construction with a vapor pressure-equalized seal.

• Lay bituminous vapor barrier/temporary seal; if required, apply the leveling layer beforehand. • Place the timber construction, affix the temporary seal all the way to the outside and blow out the hollow spaces

Existing building stock: Woodchip concrete composite block wall – metal roof sheeting on gang nail truss Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The parapet and timber construction of the roof will be removed. • The external wall will be thermally renovated by a prefabricated timber construction that is blown out with cellulose insulation on site. • The roof will be renovated with a duo roof.

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Building tasks D70 | Cavity brick wall with a clinker façade, filled, internal insulation – top story ceiling, insulated under the tiled roof, verge

Suitability • If protection against driving rain exists or can be constructed

• Clean the inner side of paint residues, etc.; fully bond, fill the interior insulation • Tightly lay the rock wool; lay the EPV panel on top of it

Construction process • Clean the exterior façade, hydrophobize the façade. Be mindful that the existing masonry is dry enough. • Fill the interstice of the cavity structure with perlite

Discussion No wind barrier will be added. Make sure there is sufficient rear ventilation of the roof space.

Existing building stock: Highly porous clay block external wall with clinker brick facing – tiled roof Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The thermal wall will be thermally renovated by an interior insulation and by filling in the hollow space with perlite insulation (see page 48). • The top story ceiling will be covered with pressure-resistant rock wool and an EPV panel. The roof space must remain rear-ventilated.

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Buildings of the 1970s D71 | Cavity brick wall with a clinker façade, filled, internal insulation – top story ceiling, insulated under the tiled roof, eaves

Suitability • If protection against driving rain exists or can be constructed

• Clean the inner side of paint residues, etc.; fully bond, fill the interior insulation • Tightly lay the rock wool; lay the EPV panel on top of it

Construction process • Clean the exterior façade, hydrophobize the façade. Be mindful that the existing masonry is dry enough. • Fill the interstice of the cavity structure with perlite

Discussion No wind barrier will be added. Make sure there is sufficient rear ventilation of the roof space.

Existing building stock: Highly porous clay block external wall with clinker brick facing – tiled roof Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The external wall will be thermally renovated by an interior insulation and by filling in the hollow space with perlite insulation. • The top story ceiling will be covered with pressure-resistant rock wool and an EPV panel. The roof space must remain well-ventilated.

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Building tasks Details roof: Internal wall – roof D72 | Concrete block internal wall – flat roof with vapor pressure-equilized insulation

Suitability

• Lay the vapor-permeable roofing sheet, weld the joints

• If the existing timber construction is suitable structurally and height-wise • If the reinforced concrete slab is airtight (e.g., in-situ concrete) Construction process • Remove metal roof sheeting, open the timber cladding in parts

• Lay the counter battens, nail on the timber cladding, attach the roof seal and metal roof sheeting Discussion As an alternative, remove the parapet and put in soundproof insulation.

• Keep existing thermal insulation, if possible. Insulate the interstice with fiber insulation material, close the openings again.

Existing building stock: Concrete block internal wall – reinforced concrete flat roof with sheet metal roofing, internally drained Preliminary questions • Is the timber construction of the roof further usable? • Is the reinforced concrete slab airtight? Description of the renovation • The timber construction of the roof will be preserved, partially opened and insulated. The metal roof sheeting will be replaced by a vapor pressure-equalized/rear-ventilated metal roof sheeting. • The structural slab is the airtight layer.

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Buildings of the 1970s Details window: External wall – window D73 | Woodchip concrete composite block external wall with ETICS – passive house wood-aluminum window

Suitability • If historic building preservation reasons do not speak against it Construction process • The airtight layer is the existing exterior plaster; close the cracks or, if necessary, fill the entire surface. • Create clean/airtight surfaces on the broken out areas of the existing windows by means of leveling screed/plaster mortar. These bond the existing exterior plaster and interior plaster airtight.

• The windows are affixed and sealed with a fleece-laminated butyl rubber strip on all sides on the plaster of the reveal and plastered over. Discussion Shortened aluminum shells and thicker added insulation lower the thermal bridge loss.

Existing building stock: Woodchip concrete composite block wall – wood composite windows Preliminary questions • Is there a window rabbet on the external wall? • What is the position of the window in the reveal? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The windows will be replaced by wood-aluminum passive house windows set into the insulation level. • The existing exterior plaster, which is connected airtight onto the interior plaster, is the continuous airtight layer. The sash seal of the window is connected to the leveling screed/plaster.

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Building tasks Details balcony: External wall – balcony D74 | Woodchip concrete composite block wall with ETICS – loggia (horizontal section)

Suitability

Discussion

• If a reduction of the loggia surface is acceptable Construction process

Due to its significantly improved mechanical stability, thick plaster is advantageous.

• T he exterior plaster is the airtight layer. If necessary, connect the completely filled exterior plaster to the loggia partition walls. • Bolt the railing onto the pressure-resistant insulation blocks • Mechanically secure the corners

Existing building stock: Woodchip concrete block external wall – reinforced concrete loggia wall Preliminary questions • What is the depth and width of the loggia? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The side walls of the loggia will likewise be insulated by a thermal insulation composite system.

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Buildings of the 1970s D75 | Woodchip concrete composite block wall with ETICS – balcony/loggia, insulated on all sides

Suitability • If a reduction of the loggia surface is acceptable

• Lay rubber granulate mat to improve the impact sound protection and to protect the seal Discussion

Construction process • Remove tiles and screed • The exterior plaster is the airtight layer. If required, completely fill it. Connect it to the balcony slab.

Due to its significantly improved mechanical stability, thick plaster is advantageous. Make sure that the thermal insulation has a low dynamic stiffness. In multi-story housing construction, impact sound insulation is possibly required under the seal.

• Lay pressure-resistant thermal insulation, lay seal all the way up to the external wall

Existing building stock: Woodchip concrete block external wall – reinforced concrete loggia wall Preliminary questions • Is the wall damp? Is there a seal and is it intact? • What is the depth and width of the loggia/balcony? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The balcony slab will be insulated on all sides.

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Building tasks D76 | Woodchip concrete composite block external wall – Wood-aluminum passive house door as balcony door – reinforced concrete balcony/loggia, insulated on all sides

Suitability • If a reduction of the loggia surface is acceptable

• Lay rubber granulate mat to improve the impact sound protection and to protect the seal • A drainage gutter is needed to lower the threshold.

Construction process • Remove tiles and screed

Discussion

• The exterior plaster is the airtight layer. If required, completely fill it. Connect it to the balcony slab.

In addition to a suitable window profile, a canopy acc. to ÖNORM B 7220 is required for a barrier-free exit. Make sure that the thermal insulation has a low dynamic stiffness. In multistory housing construction, impact sound insulation is possibly required under the seal.

• Lay pressure-resistant thermal insulation, lay seal all the way up to the external wall

Existing building stock: Woodchip concrete composite block wall – reinforced concrete balcony/loggia – wood composite windows above and below Preliminary questions • Is the wall damp? Is there a seal and is it intact? • What is the depth and width of the loggia? Description of the renovation • The external wall will be thermally renovated by an ETICS. • The balcony slab will be insulated on all sides.

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Buildings of the 1980s Buildings of the 1980s

Reinforced steel wall in contact with the ground

The construction methods of the 1980s are similar to those of the 1970s; the qualities of thermal and acoustic insulation are increased further.

Characterization of the existing building stock In large-volume housing construction, the reinforced concrete building method (using in-situ concrete or prefabricated components) finally becomes prevalent. In the single-family housing sector, a variety of well-insulated monolithic external walls are used. Insulation materials are increasingly added in walls and roofs. The thicknesses of these materials, however, are still relatively low. Single-family houses constructed with prefabricated timber components begin to spread.

Bituminous seals are the state of the art from now on. Lightweight external wall

External walls and walls in contact with the ground Reinforced concrete walls receive approx. 4 to 6 cm of thermal insulation on the outside (ETICS), or behind rear-ventilated fiber cement or sheet metal façades. Brick masonry with clinker brick facing

Prefabricated external wall, plastered with relatively good thermal protection.

Basement ceiling slab The basement ceiling slabs are similar to those from the 1970s, except for slightly higher insulation thicknesses. Reinforced steel pre-cast ceiling slab The air space is rear-ventilated outwards. A cavity wall with core insulation is constructed relatively frequently as well. Reinforced concrete with rear-ventilated facing shell made of fiber cement panels

Brick element ceiling slab

The inner layer with wood wool lightweight panels also serves as an installation shell. Brick masonry

The format sizes of the solid bricks and bonds vary depending on the region.

Floor in contact with the ground A basement is usual and in many cases the basement is used as a living space, party room, etc. A concrete slab of at least 10 cm thickness, poured onto a hardcore base, is standard. Bituminous sealing is used as a standard feature. Prefabricated houses frequently do not have a basement.

Internal walls

The degree of porosity influences the thermal insulation in a substantial way.

Details of Passive Houses: Renovation

The load-bearing internal walls are constructed for the most part like the external walls. Lightweight walls made of multi-layered gypsum plasterboard/fiberboard walls or gypsum planks find wider use.

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Wood insulating glass window

In multi-story housing construction, reinforced ceiling slabs are almost exclusively used. Suspended ceilings are also executed in single-family house construction.

Top story ceiling The top story ceiling as a thermally insulating cover is being increasingly replaced by a converted attic floor.

Roof From now on, roofs are frequently a part of the thermally-insulating cover. They are correspondingly insulated and constructed as cold roofs with rear-ventilated, bituminized felt. Roof coverings are similar to those of the 1970s. Gypsum plasterboard and gypsum fiber panels are increasingly used in interiors. Tiled roof, specialist timber construction

The standard format is the 68 mm profile.

Defects/Types of damage The following types of damage are typical for buildings of the 1980s: • Low acoustic insulation • Moisture damage on flat roofs, missing vapor pressure equalization, mold damage inside on the building corners due to sealed windows • Façade: Chipping plaster because of the thermally insulating façade or vapor-proof exterior plasters with cracks

Renovation tasks In contrast to older buildings, timber cladding and a bituminous covering are attached.

• External insulation is unproblematic because there is no ornamentation; milling off existing synthetic resin plasters may be required.

Prefabricated tiled roof

• Flat roof renovation • Possible loft conversion, new terraces • Window renovation: Replacement of the glazing and/or, depending on the condition and material, the frame as well • Insulation of the basement ceiling slab, minimization of thermal bridges across external walls and internal walls, stairwell • Improvement of airtightness • Improvement of acoustic insulation to the outside (windows and window junctions)

All layers that are not absolutely necessary (full siding on the exterior) are dispensed with for economic reasons.

• Improvement of acoustic insulation between living units (walls, ceilings)

Reinforced concrete bitumen flat roof

• Improvement of fire protection between the living units • Optimized room ventilation

Flat roofs spread rapidly and are also increasingly constructed as inverted roofs.

Window In addition to wood frames, PVC and aluminum windows increasingly come on the market. Most of the time, the thermal protection is not as good as it is with wood windows. Triple-pane insulation glazing is also used more and more. Coated panes or noble gas fillings first appear on the market in the 1990s.

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Buildings of the 1980s Base details: External wall – basement ceiling slab D77 | External brick wall with ETICS, inside – basement ceiling slab with ETICS, lower side

Suitability

• Bond the insulation panels on the basement ceiling and, depending on the subsurface, additionally dowel them

• With low exposure to rising damp • If penetrating moisture from outside (driving rain) can be surely ruled out (hydrophobization) • If an external renovation (e.g., because of historic building preservation) is not possible Construction process

Discussion Execute all interior insulation, especially in the external wall area, but only in the case of proven applicability (see page 48). Particularly suitable for “dry” basements with moisture reserves, where no high requirements are placed on the moisture behavior.

• I n case it only exists in parts, extend the existing interior plaster as the airtight layer up to the ceiling slab.

Existing building stock: Brick masonry with clinker brick facing – reinforced concrete slab with grating Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation The external wall will be thermally renovated on the inside by a thermal insulation composite system, the basement ceiling slab on the lower side with a thermal insulation composite system and the basement wall on the inside by perimeter insulation. • The temperature of the basement room decreases in the winter on account of the insulation. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks D78 | Reinforced concrete external wall with prefabricated thermal insulation box – basement wall, insulated on the exterior – basement ceiling slab with suspended ceiling and mineral wool insulation

1

Suitability

• Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone)

• With low exposure to rising damp Construction process • Create a clean surface (plaster base coat) before applying the vertical seal • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the vertical seal. Bituminous slurry is to be used in the seal area.

• Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge Discussion Particularly well-suited for higher requirements on the quality of the room air conditions in the basement

Existing building stock: Reinforced concrete wall, timber lathing – reinforced concrete slab Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation • The external wall will be thermally renovated by affixing a prefabricated mineral wool insulation box on the outside. • The basement ceiling slab will be insulated on the lower side with a suspended ceiling and glass wool insulation, the basement walls will be insulated externally. • The temperature of the basement room increases in the winter on account of the insulation. This results in a lower relative humidity when the moisture sources remain constant and is advantageous for storage. The temperature is lowered in the summer, so a combination with intelligent basement ventilation makes sense (see page 26).

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Buildings of the 1980s D79 | Brick external wall with insulation between timber construction – externally insulated basement wall – basement ceiling slab with suspended ceiling and mineral wool insulation

Suitability

• Tightly bond the seal on the complete surface up to at least 30 cm above ground level (splash zone)

• With low exposure to rising damp Construction process • C reate a clean surface (plaster base coat) before applying the vertical seal • Seal the airtight layer (exterior plaster, fully filled if required) all the way to the lower edge of the ceiling. This also provides a clean surface for applying the vertical seal. Bituminous slurry is to be used in the seal area.

• Press the perimeter insulation panels with expanding foam seals and affixed strips of fibrous insulation material upwards; the top insulation panel should be completely bonded. • Tightly seal (e.g., torch down) the polymer bitumen membranes between the upper edge of the base insulation and the insulation of the rising masonry with the wall surface; seal on the underside of the façade insulation board and drip edge

Existing building stock: Brick masonry – brick ceiling Preliminary questions • Rising damp, efflorescence? • Usage of the basement: Storage room, unused? • Type of surface, soil: Grass, gravel, sealed pavement; slanted to the outside? Description of the renovation • The external wall will be thermally renovated by affixing a prefabricated mineral wool insulation box on the outside. • The basement ceiling slab will be insulated on the lower side, the basement walls will be insulated externally and internally. • The temperature of the basement room decreases in the winter on account of the insulation. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks Details parapet: External wall – roof D80 | Porous clay block external wall with insulation between prefabricated timber construction – tiled roof

Suitability • For roofs that are adequately dimensioned in a structural sense Construction process • Uncover the roof, insulate the air space between the existing rafters, mount the timber cladding, bond the vapor barrier airtight with the existing exterior plaster of the wall

• Completely bond the top layer insulation panels in order to safely rule out an upward vapor release in the separating layer between the existing plaster and the insulation panels Discussion The execution of the replicated eaves of the façade at the same height as in the original retains the proportions of the façade.

• Attach the assembly component in the eaves area; mount the fillets, like in the existing building stock, in the edge area for the large-dimensioned canopy; add over-rafter insulation, wood fiberboard and wind barrier.

Existing building stock: Plastered brick external wall – tiled roof Preliminary questions • Are the rafters structurally adequate? Description of the renovation • The external wall will be thermally renovated by an external thermal insulation composite system. • The roof will be opened from the outside, the layers between the rafters insulated. Insulation will be placed above the over-rafters. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Buildings of the 1980s D81 | External wall with prefabricated insulation box – reinforced concrete duo roof

Suitability

Discussion

• For roofs that are adequately dimensioned in a structural sense Construction process

For a thermal bridge-optimized connection, remove the reinforced concrete parapet, if structurally possible.

• The existing gravel layer will be removed from the roof and a new seal layer and the remaining building component layers applied afterwards.

Existing building stock: Reinforced concrete external wall, timber lathing – reinforced concrete flat roof Preliminary questions • Is the ceiling construction structurally usable? Description of the renovation • The external wall will be thermally renovated by affixing a prefabricated mineral wool insulation box on the outside. • The existing gravel layer will be removed from the roof and a new seal layer and the remaining building component layers applied afterwards. • The airtight layer is the exterior plaster, which is bonded in an airtight manner with the vapor barrier in the roof.

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Building tasks D82 | Brick wall with ETICS on the inside – reinforced concrete duo roof

Suitability

Discussion

• For roofs that are adequately dimensioned in a structural sense Construction process

For a thermal bridge-optimized connection, remove the reinforced concrete parapet, if structurally possible.

• R aise the clinker façade by 3 bricks • The existing gravel layer will be removed from the roof and a new seal layer and the remaining building component layers applied afterwards.

Existing building stock: Brick masonry with clinker brick facing – reinforced concrete roof Preliminary questions • Is the ceiling construction structurally usable? Description of the renovation • The external wall will be thermally renovated by a thermal insulation composite system on the inside (see page 48). • The existing gravel layer will be removed from the roof and a new seal layer and the remaining building component layers applied afterwards. • The airtight layer is the interior plaster, which is bonded in an airtight manner with the reinforced concrete ceiling.

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Buildings of the 1980s Details base: Lightweight external wall – basement ceiling slab D83 | External wall with lightweight prefabricated component insulation element – basement ceiling slab with ETICS on the lower side

Suitability • If vertical uprights are locatable and structurally suitable Construction process • Excavation depth depending on the structural possibilities • The exterior plaster of the basement wall, resp., the seal is the airtight layer. The vapor barrier above it provides protection for the airtight material layer.

• Dowel the base plate on the basement wall, reinforce approx. every 60 cm with laminated veneer lumber • Bond the vapor barrier strips to the exterior plaster, fasten it onto the base plate, bond the drop seal onto it • Fasten insulation mat on the inside onto the prefabricated lightweight insulation element, place it onto the base plate; bolt it from below and on the side on the prepared assembly component and on the top onto the existing building stock (see eaves/verge detail).

Existing building stock: Plastered lightweight external wall – prefabricated reinforced concrete slab Preliminary questions • Is the basement damp? Is the seal there and is it intact? • Usage of the basement: Storage room, unused? Description of the renovation • The external wall will be thermally renovated by a prefabricated lightweight component fastened to the basement wall and the external wall. • The temperature of the basement room decreases in the winter on account of the insulation. This results in a higher relative humidity when the moisture sources remain constant.

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Building tasks Details external wall corner: External prefabricated lightweight wall – External lightweight wall D84 | External wall with lightweight prefabricated component insulation element – plastered prefabricated lightweight wall, variant 1

Suitability

• Fill the open area, close the assembly opening, plaster the external wall with a system corner profile

• For façades that can be externally insulated

Discussion

Construction process • Calculate the load-bearing structure of the wall; determine the grid for prefabricated components • Set wall element; fasten it in places with brackets to protect against wind suction, etc.

It is also possible to directly bond the vapor barriers of both elements over the corner; execute it in the corner area, however, as an airtight, vapor-permeable foil.

• Bond the vapor barrier of a wall element in an airtight manner onto the principally airtight OSB panel of the other wall element

Existing building stock: Plastered lightweight external wall corner Preliminary questions • Are the wall uprights still structurally usable? Description of the renovation The renovation of the external wall will be executed with insulated prefabricated wall components which provide an airtight layer on the inside.

• The airtight layer is the newly laid vapor barrier in both prefabricated components, which are connected in an airtight manner over an assembly opening.

1, 2, 3: Different versions of the existing building stock

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Buildings of the 1980s D85 | External wall with lightweight prefabricated component insulation element – plastered prefabricated lightweight wall, variant 2

Suitability • For façades that can be externally insulated Construction process • Calculate the load-bearing structure of the wall; determine the grid for prefabricated components • Set wall element (left); fasten it in places with brackets to protect against wind suction, etc. • Bond a vapor barrier cloth onto the principally airtight OSB panel (watch out for panel joints)

• Set the second element, mount it by means of brackets, bond the vapor barrier in an airtight manner with the existing vapor barrier cloth of the other element • Fill the open area, close the assembly opening, plaster the external wall with a system corner profile Discussion It is also possible to directly bond the vapor barriers of both elements over the outside; however, the airtight foil in the corner area has to be executed as a vapor-permeable foil

Existing building stock: External wall corner of plastered lightweight prefabricated wall Preliminary questions • Are the wall uprights still structurally usable? Description of the renovation The renovation of the external wall will be executed with insulated prefabricated wall components which provide an airtight layer on the inside. • The airtight layer is the newly laid vapor barrier in both prefabricated components, which are connected in an airtight manner over an assembly opening.

1, 2, 3: Different versions of the existing building stock

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Building tasks D86 | External wall with lightweight prefabricated component insulation element – External wall with ETICS with vacuum insulating panels

Suitability

• Bond the vapor barrier cloth onto the filled exterior plaster

• For façades that can be insulated on the exterior, if required for space reasons

• Bond the laminated vacuum insulation • Fill the open area, close the assembly opening, plaster the external wall with a system corner profile

Construction process alculate the load-bearing structure of the wall; determine the • C grid for prefabricated components • Completely fill the exterior plaster in the wall area of the vacuum insulation and create an even surface

Discussion A mechanical protection of the vacuum insulation with a metal lamination is worth considering.

• Set wall element (left); fasten it in places with brackets to protect against wind suction, etc.

Existing building stock: Plastered lightweight external wall corner Preliminary questions • Are the wall uprights still structurally usable? Description of the renovation • The renovation of the standard external wall will be executed with insulated prefabricated wall components which provide an airtight layer on the inside.

• The other external wall side will be renovated for space reasons with laminated vacuum insulation (entrance door area).

1, 2, 3: Different versions of the existing building stock

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Buildings of the 1980s D87 | External wall with lightweight prefabricated component insulation element, plastered, rear-ventilated – renovation with lightweight prefabricated component

Suitability • For façades that can be externally insulated Construction process • Calculate the load-bearing structure of the wall; determine the grid for prefabricated components, place the assembly component

• Set the top wall element, mount it laterally on brackets, close the vapor barrier in an airtight manner by means of the drop seal • Connect the exterior plaster and the wind seal by means of vaporpermeable adhesive tape, which is plastered into the exterior plaster by means of a reinforcement lug, so that it is windproof.

• Set wall element on the bottom; fasten it in places with brackets to protect against wind suction, etc.

Existing building stock: Plastered lightweight external wall Preliminary questions • Are the wall uprights still structurally usable? Description of the renovation The renovation of the external wall will be executed with insulated, prefabricated wall components that feature an airtight layer on the inside. • These elements are externally plastered in the lower area and executed with spaced cladding in the upper area. • The airtight layer is the newly laid vapor barrier in both prefabricated components, which are connected in an air-tight manner by means of a drop seal.

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Building tasks Details parapet: External lightweight wall – heated roof D88 | External wall with plastered lightweight prefabricated component insulation element – prefabricated roof with tile covering (eave)

Suitability • For façades and roofs that can be externally insulated Construction process • C alculate the load-bearing structure of the wall; determine the grid for prefabricated components • Uncover the roof, reuse the glass wool, if possible, otherwise dispose of it; subsequently insulate the air space between the existing rafters

• Fasten assembly component in the eaves area, set wall element, fasten it in the eaves area in places with brackets to protect against wind suction, etc. • Set roof element, including roof tile covering; bond the vapor barriers of the roof and wall so that they are airtight • Fill corner area with insulation, close the assembly opening, plaster the exterior wall with a windproof connection in the eaves area (system connection)

Existing building stock: Lightweight prefabricated wall – lightweight roof with tile covering (eaves) Preliminary questions • Are the wall uprights and rafters still structurally usable? Description of the renovation • The renovation of the external wall will be executed with insulated, prefabricated wall components that feature an airtight layer on the inside. • The roof will be opened from the outside, the existing thermal insulation will normally be disposed of, since it is no longer usable, the layer between the rafters will be insulated, the insulation is effected by means of the prefabricated roof elements (up to the wind barrier). • The airtight layer is the newly laid vapor barriers in the wall and roof, which are connected in an airtight manner in the eaves area.

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Buildings of the 1980s D89 | Plastered lightweight prefabricated wall – prefabricated roof with tile covering (verge)

• Uncover the roof, reuse the glass wool, if possible; otherwise dispose of it; subsequently insulate the air space between the existing rafters • Fasten assembly component in the eaves area, set wall element, fasten it in the eaves area in places with brackets to protect against wind suction, etc.

Suitability • For façades and roofs that can be externally insulated Construction process • Calculate the load-bearing structure of the wall; determine the grid for prefabricated components

• Set roof element, including roof tile covering; bond the vapor barriers of the roof and wall so that they are airtight • Fill in corner area, close the assembly opening, plaster the exterior wall with a windproof connection in the eaves area (system connection)

Existing building stock: Lightweight external wall – lightweight tiled roof (verge) Preliminary questions • Are the wall uprights and rafters still structurally usable? Description of the renovation • The renovation of the external wall will be executed with insulated, prefabricated wall components that feature a waterproof layer on the inside. • The roof will be opened from the outside, the existing thermal insulation will normally be disposed of, since it is no longer usable, the layer between the rafters will be insulated, the insulation is effected by means of the prefabricated roof elements (up to the wind barrier). • The airtight layer is the newly laid vapor barriers in the wall and roof, which are connected in an airtight manner in the eaves area.

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Building tasks Details roof: roof – roof D90 | Roof, insulated with prefabricated timber components, roof tile covering, component joint

Suitability • For structurally suitable roofs Construction process alculate the load-bearing structure of the wall. Most of the time • C a structural reinforcement of the ridge purlin is required. • Determine the grid for prefabricated components • Uncover the roof, reuse the glass wool, if possible, otherwise dispose of it; subsequently insulate the air space between the existing rafters • Set roof elements; ensure the airtight layer by means of compressible sealing tapes. Bond the windproof seal and secure it with counter battens and the roof tile covering.

Existing building stock: Lightweight tiled roof Preliminary questions • Are the rafters still statically usable? Description The roof will be opened from the outside, the existing thermal insulation will normally be disposed of, since it is no longer usable, the layer between the rafters will be insulated; the prefabricated roof elements, including a vapor barrier and wind barrier, guarantee an insulation that meets passive house standards. • The airtight layer is the newly laid vapor barriers in the roof, which are connected in an airtight manner with airtight and vaporproof layers in the joint area.

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Buildings of the 1980s D91 | Roof, insulated with prefabricated timber components, roof tile covering, component joint

Suitability

• Set roof elements; ensure the airtight layer by means of a compressible sealing tape in the ridge area. Bond the windproof seal and secure it with counter battens and the roof tile covering.

• For structurally suitable roofs Construction process • Calculate the load-bearing structure of the wall • Most of the time a structural reinforcement of the ridge purlin and other load-bearing parts is required.

Discussion As an alternative, an assembly opening in the ridge area is also possible for the airtight connection in the ridge area, but involves considerably more effort.

• Determine the grid for prefabricated components • Uncover the roof, reuse the glass wool, if possible; otherwise dispose of it; subsequently insulate the air space between the existing rafters • Construct a mounting plate in the ridge area

Existing building stock: Tiled lightweight roof ridge Preliminary questions • Are the rafters still statically usable? Description The roof will be opened from the outside, the existing thermal insulation will normally be disposed of, since it is no longer usable, the layer between the rafters will be insulated; the prefabricated roof elements, including a vapor barrier and wind barrier, guarantee an insulation that meets passive house standards. • The airtight layer is the newly laid vapor barrier in the roof, which is connected in an airtight manner in the eaves area.

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Building tasks Details window: External lightweight wall – window D92 | Plastered prefabricated lightweight wall – wood-aluminum window, insulatable

Suitability • If the window layer can be moved out somewhat Construction process • Calculate the load-bearing structure of the wall; determine the grid for prefabricated components

• The airtight layer is the vapor barrier in the wall element, which is sealed on all sides onto the window frame with a butyl rubber strip. • Connect the windproof layer of the plaster with the expanding foam compression tape/plastering rail onto the window frame

• Install and seal the windows in prefabricated components at the factory; deliver and mount prefabricated components

Existing building stock: Plastered lightweight external wall – wood window with insulating glass Preliminary questions • What is the position of the window in the reveal? Description of the renovation • The renovation of the external wall will be executed with insulated, prefabricated wall components that feature an airtight layer on the inside. • The windows are already mounted into the prefabricated elements on the room side and are insulated on the outside with wood fiber insulation material. • The airtight layer is the newly laid vapor barrier in the wall, which is connected in a waterproof and airtight manner onto the window frame.

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Buildings of the 1980s Details door: External lightweight wall – door D93 | Plastered prefabricated lightweight wall – passive house wooden door, insulatable

Suitability • If the position of the door cannot be changed Construction process • Clean the exterior plaster, execute the leveling screed in the connection area of the door • Set the door; connect it in an airtight and waterproof manner with a fleece-laminated butyl rubber strip onto the leveling screed • Completely fill the exterior plaster and adhesive strip and create an even surface

• Place the EPS-laminated vacuum insulation (expanding foam compression tape in the connection area that protects against driving rain); plaster with silicate plaster • Connect the windproof layer of the plaster with the expanding foam compression tape/plastering rail onto the door Discussion Shortened aluminum shells and thicker added insulation lower the thermal bridge loss.

Existing building stock: Plastered lightweight wall – wooden entrance door Preliminary questions • What is the position of the door in the wall layer? Description of the renovation • The renovation of the external wall will be executed with insulated, prefabricated wall components that feature an airtight layer on the inside. • The passive house door will be mounted on site into the prefabricated elements on the room side and insulated on the outside with wood fiber insulation material. • The airtight layer is the newly laid vapor barrier in the wall, which is connected in an airtight and waterproof manner onto the door.

i inside, a outside

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Functional units & ecological optimization

4 Functional units and ecological optimization

Insulation: Overview and ecological evaluation

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External thermal insulation of external walls

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Inner-sided thermal insulation of external walls

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Thermal insulation of pitched roofs

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Thermal insulation of flat roofs

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Thermal insulation of the top floor ceiling

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Thermal insulation of the basement ceiling on the upper side

250

Thermal insulation of the basement ceiling on the lower side

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Thermal insulation of the floor in contact with the ground

258

Thermal insulation of the outer side of the external wall in contact with the ground

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Windows 275

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Functional units & ecological optimization Functional units and ecological optimization The observation of standard cross sections and functional units enables a comparative technical and ecological evaluation of the renovation variants: • In the existing building stock as well as in the renovation, the standard cross section depicts 1 m2 of building component construction, a window or 1 m of balcony. • The functional unit is based on the same reference size, but focused on the main function of the renovation measure, which is standardized within a cross section of the same reference size. In most cases, this is the thermal insulation. The reference is the incorporation of 1 m of balcony only in the case of the balcony. The suggested functional units should be suitable for reaching the primary renovation goal of thermal insulation, but for also creating a living space that is optimized in regard to energy, building ecology and domestic hygiene, and solid as far as building physics are concerned. The following criteria will be used for the evaluation Adaptability of the existing building stock situation: • Unevenness • Coating of the existing building stock • Dirt, etc. Technical construction characteristics: • Degree of prefabrication • Necessary knowledge about the existing building stock (very precise knowledge of prefabrication) • Fastening of light (lamps) or heavy objects (photovoltaic modules, solar collectors) Physical construction characteristics: • Thermal insulation • Influence on the moisture behavior • Possible airtightness • Windtightness • Acoustic insulation • Fire protection Ecological characteristics; effect on the room climate • Ecological cost for manufacturing and maintenance • Indications of problematic substances • Required resources and emissions during installation, exposure during work • Emissions during use, useful life • Deconstruction, reutilization and recycling, disposal

Insulation: Overview and ecological evaluation Insulation from mineral raw materials Foam glass

Description Foam glass consists of expanded glass beads which are produced from waste glass. It can be used as a nonstressed fill material or as an aggregate in the manufacture of lightweight concrete, lightweight plaster, light masonry mortar or lightweight panels. The cleaned waste glass is ground into glass powder, formed into round grains and expanded at around 850 °C. The granules have a closed lattice structure and can be produced in grains of between 0.04 and 16 mm. Environmental and health impac t The foamed glass can also be produced using fragments of waste glass with grains ranging from 8 mm down to glass dust. These fragments of waste glass are rejected from the bottle recycling process. The manufacture of foam glass thus contributes to the completeness of the recycling process. However, the high temperature of expansion means that manufacture is also a relatively energy intensive process. There is no need for the use of biocides, flame retardants or other additives. Foam glass contains no fibers and no harmful substances are given off into the ambient air. Care is to be taken during the production process due to the development of dust. Recycling is possible in principle through the melting of clean foam glass. It should be disposed of on an inert materials disposal site in line with the EU Disposal Guidelines or a building material disposal site in line with the Austrian Disposal Regulations. Granulated foam glass

Description Granulated foam glass is a granular closed cell insulating material made from ground waste glass. In building projects, granulated foam glass can be used as a lightweight aggregate for concrete, as a perimeter

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Functional units & ecological optimization insulation below floorplates or laterally to basement walls and on accessible building elements with basements. As the air cells are closed the granules absorb no water. However, water can seep unhindered between the stones. Granulated foam glass is fire and heat-resistant and resistant against salts, acids, bacteria and other environmental influences. Waste glass is the source material for the manufacture of granulated foam glass. The pre-sorted waste glass passes through a multi-stage crushing and grinding process until it has been ground into a fine glass powder which is then expanded into foam glass panels at temperatures of around 900 °C. The addition of silicon carbide supports this process. The finished panel either breaks due to thermal stress during the cooling process or is actively broken down to the required grain size. The air space ratio can be varied in line with the desired product quality. A higher air ratio improves the insulating characteristics and reduces weight but also reduces the compressive strength. Environmental and health impac t The use of waste glass saves mineral resources and avoids the high-energy production of new glass. Granulated foam glass contains no fibers and no harmful substances are given off. Care is to be taken during the production process due to the development of dust. It should be disposed of on an inert materials disposal site in line with the EU Disposal Guidelines or a building material disposal site in line with the Austrian Disposal Regulations. Mineral foam panels

Description Mineral foam panels are autoclaved insulating panels for use in thermal insulation composite systems. They are also used as fiber-enriched mineral foam panels for internal insulation in refurbishment projects in the form of calcium silicate panels. They are produced from quartz sand, lime, cement, water and pore-forming additives such as (recycled) aluminum powder. The panels are bulk waterproofed and coated. The raw materials are combined into a light, ultra-porous mix. The (cake of) foam mass then cures in forms. Finally, the semi-rigid raw block is wire-cut into individual panels and hardened in autoclaves. After cutting and coating the panels are dried at 50–60 °C to 5 % humidity. Environmental and health aspec ts Mineral foam panels are manufactured in a comparably low-emission and low-energy process with no production waste and exhibit a good ecological balance. Their environmental impact is largely related to their constituent products cement and burnt lime. During the production process normal dust protection precautions should be taken. During use no substances damaging to health are released into the ambient air. The products cannot be returned to the raw material stage and can only be recycled as a finished material. Residue (cuttings) from the production process which is not yet hard can be used as a raw material for the production of new mineral foam panels. Hardened residue can be crushed and used as a substitute for sand in the production of aerated concrete. As mineral foam panels are a relatively new product on the market there is not yet any experience about the extent to which contamination by such foreign substances as plaster and mortar residue will influence any future recycling. Waste panels can be used as granulate for ballast or reprocessed as a secondary raw material for oil and liquid binding agents, hygienic litter, covering materials, sewage sludge treatment etc. Mineral foam panels consist virtually entirely of mineral raw materials as a result of which they are – from the ecological point of view – particularly suitable for the insulation of mineral load-bearing structures due to the fact that the ability to recycle and dispose of such structures will not be compromised by the mixing of organic and non-organic materials. There is not yet a concept for the recycling of mineral foam panels. They should be disposed of on an inert materials disposal site in line with the EU Disposal Guidelines or a building material disposal site in line with the Austrian Disposal Regulations. Mineral wool insulating materials Mineral wool

Mineral wool insulation is thermal insulation made from artificial mineral fibers. It is used in the form of panels, matting and felt for virtually every aspect of the insulation of buildings and building services (important exceptions: the insulation of building perimeters and inverted roofs). In the area of building a distinction is made between glass wool and rock wool insulation. Glass wool

In order to make glass wool one uses the basic ingredients of glass making: quartz sand, feldspar, soda, boron salts, dolomite, lime, sodium nitrate, fluorspar and manganese oxide. These primary raw materials are being increasingly replaced by recycled glass. In order to give it a more stable form glass wool is normally bound with 3–9 M% urea modified phenol formaldehyde resin (formaldehyde-rich resins). Silicon or mineral oil based hydrophobizing agents (approx. 1 M%) give it an additional protection against humidity. These oils also bind the fiber dusts. The raw materials are mixed and melted together at around 1,350 °C. The molten mass is placed on a rotating spindle, squeezed through small openings on the edge of the spindle, hurled outwards, drawn downwards by gas burner nozzles arranged in a ring and spun into fine glass thread with a diameter of 4–6 μm. In the next stage of the process the fibers are sprayed with binding agent before they are transported on the production line into the molding machine where the wool is given the required thickness and density before being hardened together with the binding agent at a temperature of around 230 °C.

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Functional units & ecological optimization

Rock wool

Rock wool consists of mineral raw materials such as diabase, basalt and dolomite, etc. processed into fibers. It is usually bound with phenol formaldehyde resin to give it a more stable form. Silicon or mineral oil based hydrophobizing agents (approx. 1 M%), which also bind the fiber dusts, give it an additional protection against humidity. The mineral raw materials are melted with coke, recycling wool and small amounts of lime in a cupola furnace at a temperature of around 1,500 °C. The molten mass then flows over rapidly revolving discs where it is formed into fibers and cools. The wool is then collected and evenly distributed in layers on a conveyor to form felt. Rollers press the wool to the desired thickness and density. The rock wool is finally heated in a hardening oven in order to polymerize the binding agent. Environmental and health aspec t s The high temperatures required by the melted material demand large amounts of energy which has a negative environmental impact, especially in the case of heavy products (such as MW-PT – plaster base mineral wool – for thermal insulation composite systems). When working with mineral wool products artificial mineral fibers (AMF) can be liberated. Since 2000 only mineral fiber products free of all carcinogenic risk (see note Q and R of Directive 97/69/EG), may be manufactured and used. Airtight construction ensures that no fine fibers can enter the internal ambient air. Formaldehyde is released from the binding agent. In order to market mineral wool insulation in Austria one is required to provide proof of formaldehyde class E1 in accordance with ÖNORM EN 13986 (2005:04). Non-glued, clean and, in particular, non-carcinogenic mineral wool can be reused or recycled as packing wool. CMR materials may not be recycled. When reusing mineral wool it must also be guaranteed that the mineral fibers are non-carcinogenic. Most manufacturers will not take back demolished waste. Mineral wool waste may be disposed of on building material disposal sites or mass waste disposal sites in Austria without documented proof despite the relatively high levels of TOC (binding agents up to 9 M%) (Disposal decree, Appendix 2, List 2). So-called old mineral wool, which is rated carcinogenic, must be correctly removed and disposed of as dangerous waste. In Germany the Technical Rules for Dangerous Materials (TRGS) 521 are to be referred to as a means of protecting workers and other people during demolition, refurbishment and maintenance work involving old mineral wool. Amongst other things, these describe methods of passing on information and evaluating risk as well as outlining a concept which defines grades of exposure for activities with mineral wool in terms of the levels of fiber dust which arise and sets out the appropriate protective measures. Even if demolition, refurbishment and maintenance work involving old mineral wool in other countries are not regulated in the same way it is still recommended that one acts with precaution in line with TRGS 521. Perlite insulating panels

Description Perlite insulation panels are capillary-active insulating panels for the internal insulation of external walls and internal slabs. The panels consist of expanded perlite, cellulose and mineral binding agents. The granules of expanded perlite are manufactured as described in the chapter on perlite insulating fill. A highly viscose binding agent is manufactured from amorphous silica (binding agent) and starch (thickener) and then stored in an intermediate container. The binding agent gel is mixed with the perlite granules and pressed into a panel. The pressed green body is then transported to the dryer and dried in one go before being prepared for distribution and packed. Environmental and health aspec t s Perlite insulating panels consist exclusively of mineral and renewable raw materials. The manufacture of amorphous silica is complex – but less so than the manufacture of binding agents on the basis of synthetic resins. No environmentally dangerous substances are emitted into the ambient air during the production of the panels. The normal protective precautions against dust should be taken during the processing of the panels. No substances which endanger health are liberated into the internal ambient air during use. Perlite insulation panels have only been on the market for a few years and no evaluation procedure has yet been introduced. The current technical standards leave one to assume that the panels will be disposed of together with the mineral building waste on an inert material disposal site in line with the EU disposal guidelines or a construction waste disposal site in line with the Austrian Disposal Decree. Perlite insulating fill

Description Perlite is used as leveling or insulating fill in walls, ceilings and roofs and as the internal insulation on floor panels. Vermin and rodents can build neither tunnels nor nests in the loose fill. In addition to this, the inorganic material is resistant against chemicals, decay and microorganisms. Perlites are a family of vitreous, glassy rocks created when volcanic material comes into contact with water during periods of volcanic activity (below the sea or below ice). Perlite is mined. In Europe there are deposits in Hungary, Greece, Turkey, Sicily, Rumania, Bulgaria and Ukraine. Expanded perlite is used as an insulating fill. To produce this, perlite is briefly heated to over 1,000 °C at which point the water chemically bound with the rock suddenly evaporates and the volume of the raw material expands by a factor of 15 to 20. Depending upon the proposed use it is manufactured as pure expanded perlite, rendered water-repellent by the addition of silicon or coated in bitumen, natural resins or similar materials.

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Details of Passive Houses: Renovation

Functional units & ecological optimization Environmental and health aspec ts Sufficient amounts of perlite are available. The environmental impact of its extraction is compatible with that of the extraction of grit. The expansion procedure uses a range of processes as a result of which the expanded product has a diverse range of ecological profiles. The largest health risk during the processing of perlite comes from exposure to dust as a result of which dust protection measures are necessary. Bituminized perlite can emit organic substances. The reuse of perlite used as a fill material presents no difficulties. After cleaning and drying the material can be reused as fill material or as an additive without difficulty. It should be disposed of on an inert material disposal site in line with the EU disposal guidelines or a construction waste disposal site in line with the Austrian Disposal Decree. In the event of a bitumen coating the ecological advantages of a purely mineral product are lost. Foam glass panels

Description Foam glass panels are gas proof and vapor proof, watertight and fully moisture-resistant thermal insulating panels for internal and external building elements which come into contact with the ground and for all compression-loaded situations. Like glass, foam glass consists of the raw materials quartz sand, feldspar, limestone or dolomite and soda. Iron and manganese oxide can be used as additives and carbon is added as an expansion agent in the form of coke, magnesium or calcium carbonate. These glass raw materials are increasingly being replaced by recycled and scrap glass (over 50 % according to manufacturers). These glass raw materials are transformed into a molten mass which is extruded, crushed and ground into glass powder. The carbonate expansion agent can then be added in the form of coke, magnesium carbonate, calcium carbonate, sugar, glycerin or glycol. The mixture is then heated to around 1,000 °C. As the carbonate oxidizes gas bubbles are produced. The cooling follows a precisely defined method. The panels are either fixed to the building using mineral adhesive mortar, bituminous adhesive or hot bitumen in a way that ensures that all surfaces and joints are fully covered and filled or dry-laid in fine grit, sand or fresh concrete. Environmental and health aspec ts Manufacturing requires high energy consumption which also leads to atmospheric emissions. However, the use of recycled glass enables the energy required for production to be continuously reduced due to the fact that the melting point of recycled glass is lower than that of the mixture of raw materials. The laying of foam glass in hot bitumen results in the emission of bitumen fumes containing polycyclic aromatic hydrocarbons and other volatile organic compounds. The cutting of foam glass can release both dust which can lead to irritations of the eye and such secondary components of the gas fill as hydrogen sulfide and nitrogen which result in highly unpleasant odors but present no danger to health due to their tiny quantities. Panels laid in a sand bed can be reused if in a good condition. The high quality recycling of glued panels is, however, normally not possible due to contamination from bitumen or other adhesives (although ‘downcycling’ in the form of back filler material is possible). Foam glass panels should be disposed of on an inert material disposal site in line with the EU disposal guidelines or a construction waste disposal site in line with the Austrian Disposal Decree. Vacuum insulating panels

Description Vacuum insulation panels are highly-efficient thermal insulating panels which can be used wherever little space is available due to their low thermal conductivity (