Span Tables for Rafters (to BS 5268-7.5)

Imposed loads of 0.75 kN/m² snow load are applicable to most areas where the altitude does not exceed 100 metres (refer to BS 6399-3)

Imposed loads of 1 kN/m² snow load are applicable to most areas where the altitude exceeds 100 metres but does not exceed 200 metres, but excluding parts of Scotland, Pennines, North East England (refer to BS 6399-3)

Imposed load	Slope	Timber	Plasterboard Underneath?
0.75 kN/m²	15° or more but less than 22.5°	C16	No
0.75 kN/m²	15° or more but less than 22.5°	C24	No
0.75 kN/m²	22.5° or more but less than 30°	C16	No
0.75 kN/m²	22.5° or more but less than 30°	C24	No
0.75 kN/m²	30° or more but less than 45°	C16	No
0.75 kN/m²	30° or more but less than 45°	C24	No
0.75 kN/m²	15° or more but less than 22.5°	C16	Yes
0.75 kN/m²	15° or more but less than 22.5°	C24	Yes
0.75 kN/m²	22.5° or more but less than 30°	C16	Yes
0.75 kN/m²	22.5° or more but less than 30°	C24	Yes
0.75 kN/m²	30° or more but less than 45°	C16	Yes
0.75 kN/m²	30° or more but less than 45°	C24	Yes
1 kN/m²	15° or more but less than 22.5°	C16	No
1 kN/m²	15° or more but less than 22.5°	C24	No
1 kN/m²	22.5° or more but less than 30°	C16	No
1 kN/m²	22.5° or more but less than 30°	C24	No
1 kN/m²	30° or more but less than 45°	C16	No
1 kN/m²	30° or more but less than 45°	C24	No
1 kN/m²	15° or more but less than 22.5°	C16	Yes
1 kN/m²	15° or more but less than 22.5°	C24	Yes
1 kN/m²	22.5° or more but less than 30°	C16	Yes
1 kN/m²	22.5° or more but less than 30°	C24	Yes
1 kN/m²	30° or more but less than 45°	C16	Yes
1 kN/m²	30° or more but less than 45°	C24	Yes

Span Tables for Rafters (to BS 5268-7.5)

Calculators

Span tables

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