Preface x
1 Wood as a Material 1
1.1 Cellulose 2
1.2 Grain 4
1.3 Dimensional change in wood 8
1.4 Heartwood and sapwood 10
1.5 Natural durability 13
1.6 Rays 14
1.7 Radial and tangential directions 15
1.8 Permeability in timber 16
1.9 Chapter summary 16
2 More on Timber: Some Stuff About the UK Timber Trade 18
2.1 'Wood' or 'timber'? 18
2.2 Wood species and timber trading 19
2.3 Softwoods and hardwoods 19
2.4 Some more detail on cell structure 23
2.5 Trade names and scientific names 27
2.6 A cautionary tale about timber names 28
2.7 Growth rings 31
2.8 Earlywood and latewood 32
2.9 Rate of growth in softwoods 33
2.10 Rate of growth in hardwoods 34
2.11 Chapter summary 37
3 Water in Wood: Moisture Content and the Drying of Timber 39
3.1 The definition of moisture content 39
3.2 Moisture meters 40
3.3 'Wet' or 'dry'? In-service moisture contents and 'EMC' 43
3.4 EMC 44
3.5 Specification of desired moisture content 44
3.6 Fibre saturation point 46
3.7 Shrinkage 47
3.8 Movement 48
3.9 Kiln drying 49
3.10 Air drying 53
3.11 Timescales for drying timber 54
3.12 Chapter summary 55
4 Specifying Timber - for Indoor or Outdoor Uses 57
4.1 British and European standards 57
4.2 Durability and treatability of different wood species 58
4.3 Use classes 59
4.4 Examples of timbers employed in different use classes 60
4.5 Hazard and risk - and their relative importance 60
4.6 Use Class 1 - examples 61
4.7 Use Class 2 - examples 64
4.8 Use Class 3 - examples 66
4.9 Use Class 4 - examples 70
4.10 Use Class 5 - examples 76
4.11 Chapter summary 78
5 The Quality of Timber: Grading for Appearance 79
5.1 The need for grading 80
5.2 'Quality' or 'grade'? 81
5.3 Quality 82
5.4 Grade 82
5.5 The different types of grading 83
5.6 Appearance grading 83
5.7 Appearance grading: based on defects 83
5.8 Scandinavian grades 87
5.9 Unsorted, fifths and sixths 88
5.10 Russian softwood qualities 89
5.11 European appearance grading 90
5.12 North American softwood appearance grades 90
5.13 Clears, merchantable and commons 92
5.14 A comparison of Scandinavian grades and North American grades 93
5.15 Appearance grading: based on 'cuttings' 93
5.16 The NHLA grades 94
5.17 FAS, selects and commons 96
5.18 Selects 96
5.19 'F1F' 97
5.20 Prime and Comsel grades 97
5.21 Malaysian grades 98
5.22 Prime, select and standard 98
5.23 'PHND', 'BHND' or 'sound' 99
5.24 Rules are made to be bent! (within reason) 99
5.25 Shipper's usual 99
5.26 BS EN 942: the quality of timber in joinery 100
5.27 J classes 100
5.28 'Exposed face' 101
5.29 Chapter summary 102
6 Strength Grading and Strength Classes of Timber 104
6.1 Appearance versus strength 106
6.2 Visual strength grades 107
6.3 GS and SS strength grades 107
6.4 Strength classes for softwoods 108
6.5 BS EN 1912 108
6.6 SC3, SC4: C16 and C24 109
6.7 Machine grading 110
6.8 Other strength grades: Europe and North America 112
6.9 Select structural, No. 1 and No. 2 structural and stud grades 112
6.10 TR26 113
6.11 Specifying the strength class or the wood species: some things to think about 114
6.12 Hardwood strength grades 115
6.13 Tropical hardwoods 116
6.14 Temperate hardwoods 116
6.15 The 'Size effect' 117
6.16 Hardwood strength classes 118
6.17 The marking of strength graded timber 119
6.18 Chapter summary 120
7 Wood Preservatives and Wood Finishes 122
7.1 Treat the timber last! 122
7.2 Wood preservative types 123
7.3 'Old' and 'new' types of treatments 124
7.4 The basic methods of timber treatment 124
7.5 Low pressure treatment 125
7.6 High pressure treatment 126
7.7 Preservative chemicals 126
7.8 CCA preservatives 126
7.9 The 'environmentally-friendly' preservatives 127
7.10 'Tanalised' timber 128
7.11 Organic compounds 128
7.12 'Treated' timber 129
7.13 'Wood finishes' 129
7.14 Wood in exterior uses 130
7.15 Exterior finishes 131
7.16 Varnish - and paint 131
7.17 'Microporous' exterior stains and paints 133
7.18 Non-film-forming finishes 133
7.19 Exterior paints 134
7.20 The durability of exterior finishes 135
7.21 The effects of lighter or darker colours 136
7.22 Chapter summary 137
8 Principal Softwoods Used in the UK 139
8.1 European redwood ( Pinus sylvestris ) 139
8.2 European whitewood (mostly Picea abies ) 141
8.3 Sitka spruce ( Picea sitchensis ) 142
8.4 Western hemlock ( Tsuga heterophylla ) 142
8.5 'Douglas fir' ( Pseudotsuga menziesii ) 143
8.6 Larch (mainly Larix decidua and L. kaempferi/L. leptolepis ) 145
8.7 'Western red cedar' ( Thuja plicata ) 145
8.8 Southern pine ( Pinus spp - principally Pinus elliottii and P. palustris ) 146
8.9 Yellow pine ( Pinus strobus ) 147
8.10 'Parana pine' ( Araucaria angustifolia ) 147
8.11 Species groups 148
8.12 Spruce-pine-fir 148
8.13 Hem-fir 149
8.14 Douglas fir-larch 149
9 A Selection of Hardwoods Used in the UK 150
9.1 Ash, American ( Fraxinus spp ) 151
9.2 Ash, European ( Fraxinus excelsior ) 152
9.3 Beech, European ( Fagus sylvatica ) 152
9.4 Birch, European (mainly Betula pubescens ) 153
9.5 Cherry, American ( Prunus serotina ) 153
9.6 Chestnut, Sweet ( Castanea sativa ) 153
9.7 Ekki ( Lophira alata ) 154
9.8 Greenheart ( Ocotea rodiaei ) 154
9.9 Idigbo ( Terminalia ivorensis ) 155
9.10 Iroko ( Milicia excelsa ) 155
9.11 Keruing ( Dipterocarpus spp .) 156
9.12 Mahogany, African ( Khaya ivorensis and K. anthotheca ) 156
9.13 Mahogany, American ( Swietenia macrophylla ) 156
9.14 Maple ( Acer saccharum ) 157
9.15 Meranti ( Shorea spp .) 157
9.16 Oak, American red (principally Quercus rubra and Q. falcata ) 158
9.17 Oak, American white (principally Quercus alba, Q. prinus, Q. lyrata and Q. michauxii ) 158
9.18 Oak, European (mainly Quercus robur ) 158
9.19 Obeche ( Triplochiton scleroxylon ) 159
9.20 Opepe ( Nauclea diderrichii ) 160
9.21 Sapele ( Entandrophragma cylindricum ) 160
9.22 Tatajuba ( Bagassa guianensis ) 161
9.23 Teak ( Tectona grandis ) 161
9.24 Utile ( Entandrophragma utile ) 161
9.25 Walnut, American ( Juglans nigra ) 162
9.26 Walnut, European ( Juglans regia ) 162
9.27 Whitewood, American, or Tulipwood ( Liriodendron tulipifera ) 163
10 Wood-based Sheet Materials 164
10.1 Plywood 164
10.2 The two fundamental properties of plywood 165
10.3 Basic types of plywood 166
10.4 Conifer plywoods 166
10.5 Temperate hardwood plywoods 168
10.6 Tropical hardwood plywoods 168
10.7 Plywood glue bond and 'WBP' 169
10.8 Exterior 170
10.9 Adhesives used in plywood 171
10.10 BS 1088 marine plywood 172
10.11 Plywood face quality 172
10.12 Appearance grading of face veneers 173
10.13 Conifer plywood appearance grades 173
10.14 Temperate hardwood plywood appearance grades 175
10.15 Tropical hardwood plywood appearance grades 175
10.16 Particleboards and wood chipboard 177
10.17 Flaxboard and bagasse board 178
10.18 OSB 178
10.19 Fibreboards 181
10.20 Hardboard, medium board and softboard 181
10.21 MDF 183
10.22 Chapter summary 185
Appendices 186
1 A Glossary of Wood and Timber Terms Used in the Timber and Construction Industries 186
2 A Select Bibliography of Some Useful Technical References About Wood 200
3 Some Helpful Technical, Advisory and Trade Bodies Concerned with Timber 201
Index 202
