Flat Roof Joist Sizes C24

400mm 450mm 600mm 97 x 47 1 84 1 81 1 74 120 x 47 2 43 2 39 2 27 145 x 47 3 08 3 02 2 87.

Flat roof joist sizes c24.

These span tables apply only to flat roof and roof with a slope of up to 10 degrees. This demo version is fixed at 1m clear span. Clear spans for flat roof joists in metres. Flat roof joist calculator.

Where the tables do not apply or where there are concentrated loads floor joists should be designed by an engineer in accordance with technical requirement r5. Roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16 size of rafters in mm 400mm 450mm 600mm. 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. 1 enter joist details 1 1 span and joist spacing.

Size of roof joists spacing of joists. 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 04 2 75 3 47 4 20 4 93 5 66 floor joists flat roof joists assumptions at 400mm centers supporting permanent load excluding self weight of joists up to 50kg m2. Building control guidance note planning regulations. These tables can help calculate whether floor joists are strong enough to support themselves and the load they carry without the help of any walls underneath.

Surveyors span tables for designing roof rafters. The full version allows any size. Surveyors and structural engineers use data from tables below to help calculate the size of timbers necessary to give adequate support to timber floors. Solid timber joist sizes are provided in the bs 8103 3 span tables.

Joists under each partition. For pitched roofs flat roofs and ceiling joists. 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. Maximum clear span of flat roof joists in metres for sc3 timber spacing between joists size of roof joist 400mm 450mm 600mm 47 x 97 1 84 1 81 1 74 47 x 120 2 43 2 39 2 27 47 x 145 3 08 3 02 2 87 47 x 170 3 75 3 67 3 42 47 x 195 4 41 4 31 3 92 47 x 220 5 04 4 85 4 41 75 x 170 4 50 4 38 3 99.

Timber to be covered these span tables do not apply to timber which is fully exposed to the elements.