Roof Rafter Span Table

Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size.

Roof rafter span table.

Rafter spans for southern yellow pine douglas fir and eastern spruce. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. Surveyors span tables for designing roof rafters. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

For each application a pdf download is available. Span calculator for wood joists and rafters also available for the android os. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Also available for the android os.

Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope. Click here for structural design calculations. Tables listing maximum spans for southern pine joists and rafters are detailed below.

The shapes and spans shown here represent only a fraction of the millions of designs processed by alpine engineers. These 46 tables are based upon design values for visually graded southern pine dimension lumber that became effective june 1 2013. View joist rafter tables. So this table could accommodate a house with a total rafter span or house width of 32 feet.

Span configuration and load conditions. 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. The loads are based on adjusted roof snow loads from the governing building code. Rafter spans are tabulated for the most common roof loads.

Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. For roof live loads less than 20 pounds per square foot psf rafter spans and required e values tabulated for 20 psf shall be permitted to be adjusted in accordance with the fol lowing table.