Basic racking resistance for a range of materials and combination of materials (BS 5268-6.1:1988 (BSI, 1988) and BS 5268-6.1:1996 (BSI, 1996a))
| Primary board material | Fixing | Racking resistance: kN/m | Additional contribution of secondary board on timber frame wall: kN/m | |
|---|---|---|---|---|
| Category 2 or 3 materials | Category 1 material | |||
| Category 1 materials | 3·00 mm diameter wire nails at least 50 mm long, maximum spacing 150 mm on perimeter, 300 mm internal | 1·68 | 0·28 | 0·84 |
| 9·5 mm plywood | ||||
| 9·0 mm medium board | ||||
| 12·0 mm chipboard (type C3M, C4M or C5) | ||||
| 6·0 mm tempered hardboard | ||||
| 9·0 mm OSB/3 | ||||
| Category 2 materials | 3·00 mm diameter wire nails at least 50 mm long, maximum spacing 75 mm on perimeter, 150 mm internal | 0·9 | 0·45 | 1·06 |
| 12·5 mm bitumen-impregnated insulation board | ||||
| Separating wall of minimum 30 mm plasterboard (in two or more layers) | Each layer should be individually fixed with 2·65 mm diameter plasterboard nails at 150 mm spacings, nails for the outermost layer should be at least 60 mm long | 0·9 | 0·45 | 1·06 |
| Category 3 materials | 2·65 mm diameter plasterboard nails at least 40 mm long, maximum spacing 150 mm | 0·9 | 0·45 | 1·06 |
| 12·5 mm plasterboard | ||||
| Primary board material | Fixing | Racking resistance: kN/m | Additional contribution of secondary board on timber frame wall: kN/m | |
|---|---|---|---|---|
| Category 2 or 3 materials | Category 1 material | |||
| Category 1 materials | 3·00 mm diameter wire nails at least 50 mm long, maximum spacing 150 mm on perimeter, 300 mm internal | 1·68 | 0·28 | 0·84 |
| 9·5 mm plywood | ||||
| 9·0 mm medium board | ||||
| 12·0 mm chipboard (type C3M, C4M or C5) | ||||
| 6·0 mm tempered hardboard | ||||
| 9·0 mm OSB/3 | ||||
| Category 2 materials | 3·00 mm diameter wire nails at least 50 mm long, maximum spacing 75 mm on perimeter, 150 mm internal | 0·9 | 0·45 | 1·06 |
| 12·5 mm bitumen-impregnated insulation board | ||||
| Separating wall of minimum 30 mm plasterboard (in two or more layers) | Each layer should be individually fixed with 2·65 mm diameter plasterboard nails at 150 mm spacings, nails for the outermost layer should be at least 60 mm long | 0·9 | 0·45 | 1·06 |
| Category 3 materials | 2·65 mm diameter plasterboard nails at least 40 mm long, maximum spacing 150 mm | 0·9 | 0·45 | 1·06 |
| 12·5 mm plasterboard | ||||