Roof Joist Span Table

1 inch 25 4 mm 1 foot 304 8 mm 1 pound per square foot 0 0479kpa.

Roof joist span table.

Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. For example the highlighted cell below shows that a 2 x 6 southern yellow pine joist with a grade of 2 and spaced 24 apart can have a maximum span of 10 feet 0 inches 10 0 if you are designing your structure to support a plaster ceiling. Table r802 4 1 ceiling joist spans for common lumber species uninhabitable attics without storage live load 10 psf l δ 240 check sources for availability of lumber in lengths greater than 20 feet. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

Joist and rafter span tables. Span tables use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Also available for the android os.

Span calculator for wood joists and rafters also available for the android os. For each application a pdf download is available. These 46 tables are based upon design values for visually graded southern pine dimension lumber that became effective june 1 2013.