Timber Roof Beam Span Tables

View joist rafter tables.

Timber roof beam span tables.

Window door garage door headers supporting roof wall floor loads. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Window door garage door headers supporting roof loads only. 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.

These span tables apply only to flat roof and roof with a slope of up to 10 degrees. 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. For pitched roofs flat roofs and ceiling joists. For lesser grades spans should be shorter.

View allowable load tables. Span calculator for wood joists and rafters also available for the android os. The tables below give maximum spans for rafters and beams. Surveyors span tables for designing roof rafters.

Tables providing size selections for various beam spans and loading combinations for southern pine dimension lumber and southern pine glued laminated timber are available for the following applications. View size selection tables. The figures are based on quality materials. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Also available for the android os. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.