Span Roof Rafters

This calculator is to be used as an estimating tool only.

Span roof rafters.

The lengths and sizes of joists vary depending on the species and quality of the lumber used. Also available for the android os. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads. 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.

So this table could accommodate a house with a total rafter span or house width of 32 feet. As mentioned above a 2 4 spf shed roof rafter can span 11. An syp rafter can span 11. 2 are indicated below.

For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. The spans in this table are based on a maximum supported rafter span of 16 feet where the supported span is the total horizontal distance spanned by the roof rafters divided in half not the diagonal distance or the length of the rafter. 1 psf lb f ft 2 47 88 n m 2. Live load is weight of furniture wind snow and more.

If you look at the rafter span chart you ll notice that 2x4s can be used for rafters on spans up to 11. To size joists and rafters use the maximum span tables for southern yellow pine. The 1 grade. The pitch and span of your roof will dictate how long of a rafter you ll need use maximum span calculator to help you find your rafter size.

Span calculator for wood joists and rafters also available for the android os. Anything beyond that you are looking at using 2x6s for most sheds. Rafter stock size calculator. Dead load weight of structure and fixed loads 15 lbs ft 2.

More roof calculators roof truss calculator how to cut rafters. Wood beam calculator american wood council website rafter and joist span faq. If you live in an area that requires a shed roof rafter to support a heavy load then an spf rafter can only span 7. For example you can span a 1 grade no knots southern yellow pine a greater distance than a 2 grade with knots southern yellow pine.

This rafter span calculator is species specific for douglas fir hemlock etc. 1 ft 0 3048 m. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no. 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.

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.