Timber Roof Span Tables Uk

These span tables apply only to flat roof and roof with a slope of up to 10 degrees.

Timber roof span tables uk.

Ceiling joists flat roof joists rafters purlin span tables rafters. All the figures are based on roofing tiles or slates laid on timber laths over sarking felt. For timber floors between homes. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

Surveyors span tables for designing roof rafters. Span tables for flat roof joists to bs 5268 7 2 imposed loads of 0 75 kn m for maintenance and snow load are applicable where there is no permanent access no fixed ladder or staircase and most areas where the altitude does not exceed 100 metres refer to bs 6399 3. Notches are not to exceed 0 125 of the depth of the joist and are to be located between 0 07 and 0 25 of the span from the support. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.

Span tables for solid timber joists. They also tell you what the maximum spacing should be between each section or timber member size of joists mm clear span c16 joist m clear span c24 joist m 47 x 95 47 x 120 47 x 145 47 x 170 47 x 195 47 x. 15 or more but less than 22 5. Span tables span tables can be used to determine the size of a timber member of a particular strength class required for a given span.

Tables 1 and 2 in this chapter are derived from the trada technology ltd. Span table 0 75 kn m. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Span tables for flat roof joists to bs 5268 7 2 imposed loads of 0 75 kn m for maintenance and snow load are applicable where there is no permanent access no fixed ladder or staircase and most areas where the altitude does not exceed 100 metres refer to bs 6399 3.

Span tables for rafters to bs 5268 7 5 imposed loads of 0 75 kn m snow load are applicable to most areas where the altitude does not exceed. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. The section sizes are based on regularised als or cls timber.

Notches are not to exceed 0 125 of the depth of the joist and are to be located between 0 07 and 0 25 of the span from the support. The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.