For pitched roofs flat roofs and ceiling joists.
Roof span tables uk.
Span tables for ceiling joists to bs 5268 7 3 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.
Surveyors span tables for designing roof rafters.
These span tables are the equivalent of other industry standard span tables and are calculated to the same standards.
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.
Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run.
These spans were calculated using our flat roof joist calculation engine.
Maximum clear span of rafters in metres for roof pitches of between 15 and 45 degrees.
Contact a building control officer for advice.
Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch.
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 220 1 77 2 40 2 89 3 38 3 87 4 36 2 05 2 67 3 22 3 77 4 31 4 85 assumptions at 400mm centers.
This span table is to the format and methodology given in bs 5268 7 2.
They also tell you what the maximum spacing should be between each section or timber member.