Flat Roof Joist Span Table Uk

Surveyors span tables for designing roof rafters.

Flat roof joist span table uk. For timber floors between homes. Should refer to trada document span tables for solid timber members in floors ceilings and roofs excluding trussed rafter roofs for dwellings or ask your lbc surveyor for advice. Floor joist span tables for surveyors floor construction. This table uses commonly available uk regularised timber depths.

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. Subject ceilings and flat roofs timber sizes and construction details 09 issued 01 04 13 rev page 1 of 2 the following tables give details of the allowable spans and spacing for some of the more common timber sizes used in ceiling and flat roof construction. Span tables for solid timber joists. You need to measure the complete span of your floor joists together with the distance between them the centres and the size of the timbers.

If your old joists do not meet the requirements set by the table they are either supported. 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. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Other span tables are based on.

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. These span tables apply only to flat roof and roof with a slope of up to 10 degrees. Joists under each partition. The floor joist span tables are based on the loadings given in the amended version of bs 6399 1 which is an imposed load of either a uniformly distributed load of 1 5 kn m or a concentrated load of 1 4 kn.

This should be compared to the table. 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. The section sizes are based on regularised als or cls timber. Flat roof with no permanent access and altitude not exceeding 100m 0 75 kn m udl 0 9 kn point load most areas exceeding 100m but not exceeding 200m excluding parts of scotland pennines north east england refer to bs 6399 3 1 kn m udl 0 9 kn point load.

Eurocode 5 span tables for solid timber members in floors ceilings and roofs for dwellings 3rd edition. Flat roof joists rafters purlin. For pitched roofs flat roofs and ceiling joists.