Span Roof Rafters

Span calculator for wood joists and rafters also available for the android os.

Span roof rafters.

This rafter span calculator is species specific for douglas fir hemlock etc. 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. More roof calculators roof truss calculator how to cut rafters. Dead load weight of structure and fixed loads 15 lbs ft 2.

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. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads. An syp rafter can span 11. Both of these are for light roof loads.

If you look at the rafter span chart you ll notice that 2x4s can be used for rafters on spans up to 11. Input the rafter span on the flat eave overhang and pitch of the roof. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no. Click the button to calculate the stock size needed for this job.

This calculator is to be used as an estimating tool only. 1 psf lb f ft 2 47 88 n m 2. Rafter stock size calculator. 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.

The lengths and sizes of joists vary depending on the species and quality of the lumber used. 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. The 1 grade. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

1 ft 0 3048 m. Anything beyond that you are looking at using 2x6s for most sheds. 2 are indicated below. 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.

As mentioned above a 2 4 spf shed roof rafter can span 11. 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. To size joists and rafters use the maximum span tables for southern yellow pine. Also available for the android os.

Live load is weight of furniture wind snow and more.