Flat Roof Rafters Span Tables

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.

Flat roof rafters span tables. Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall. For pitched roofs flat roofs and ceiling joists. Posts these span tables are designed for a minimum post size of 50 x 50 x 2 5mm up to a maximum height of 3 0m. Surveyors span tables for designing roof rafters.

Ceiling joist span use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Roof pitch use recommended minimum roof pitches as specified by roof sheet supplier. 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.

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. Flat roof span tables allow for a maximum roof pitch of 5º.