Table of Contents
1 Introduction and acknowledgements 1 Acknowledgements 2
2 Roofing terminology 3
3 Calculating the size of timber members 9
Strength and section size calculations 11
How do we calculate the loading on the roof? 11
Timber member sizing design: an example 12
Cost consideration 19
4 Calculating the length and cutting angles of timber members: data tables 5 ◦ –75 ◦ 20
The pitch 23
Using the tables to cut a common rafter 23
Hip jack rafters 28
Hip rafters 30
Valley jack rafters 32
The ridge 32
Purlins 34
5 Wall plates – strapping and gable strapping 109
6 Wind bracing and openings for dormers and roof windows 111
Openings for dormers and roof windows 113
7 Roofing metalwork and fixings 119
Nails, bolts and screws 121
8 Engineered timber roofing components and prefabricated roofs 123
Trussed rafters 123
Spandrel panels 125
Crane-on roof assemblies – trussed rafters 127
Crane-on roofs – structural panels 128
Crane-on roof assemblies – structural insulated panels 128
Attic to room-in-the-roof conversion 130
9 Roof coverings – underlay, battens and tiles 134
Underlay 134
Battens 138
Insulation and ventilation 140
Choosing the roof covering 154
Building regulations – thermal performance 162
10 Roof coverings – building detail drawings 179
The new BS 5534:2014 179
Manufacturer’s specification 180
Hips, ridges, verges and valleys – traditional and new methods of construction 180
Roofing putties 187
Natural slates 189
Concrete interlocking tiles 192
Plain and peg tiles 193
Asphalt shingles 198
Metal tiles 201
Lead substitutes 202
11 Solar panels 205
Planning and roof suitability 205
Roof construction 206
Fixing the panels 207
Possible improved fixing 208
Variations on panel design 211
12 Sheds and outbuildings 212
Permitted development 212
Types of permitted building 212
Design 215
The structure 215
The mono-pitch roof 216
The dual-pitch roof 216
Roof coverings 218
Make your new building save money! 220
13 Tools and equipment 221
Obtaining information from the drawing 221
To cut the roof 222
Setting up the roof structure 222
Roof coverings 223
14 Health & safety considerations 224
Access to the roof 224
Basic principles 225
Restoration and renovation of existing roof structures 225
Newly constructed roofs 226
The roof covering 226
Conclusion 227
Bibliography 229
Index 243
