2x12x20 Treated Span Tables For Roof Rafters

Just enter the dimensions of the roof rise and run to get started.

2x12x20 treated span tables for roof rafters. View joist rafter tables. 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. The tables permit a bearing length of up to 3 5 inches but since 1 5 is probably the worst case that you ll encounter for joist or rafter bearing it s a safe value. 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.

1 when loads are applied structural members bend producing tension in the fibers along the faces farthest from the applied load and com. If you look at the rafter span chart you ll notice that 2x4s can be used for rafters on spans up to 11. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Table 9 1 in span tables for joists and rafters figure 5 gives a required compression value of 237 psi for a span of 16 feet and bearing length of 1 5 inches.

Anything beyond that you are looking at using 2x6s for most sheds. In addition fc and fv are included as a consideration for selec tion of joist and rafters. 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. Extreme fiber stress in bending fb fig.

Span tables for rafters to bs 5268 7 5 imposed loads of 0 75 kn m snow load are applicable to most areas where the altitude does not exceed 100 metres refer to bs 6399 3 imposed loads of 1 kn m snow load are applicable to most areas where the altitude exceeds 100 metres but does not exceed 200 metres but excluding parts of scotland. Also available for the android os. Span calculator for wood joists and rafters also available for the android os. If you re building rafters and aren t sure where to start when determining the length of your lumber you re in the right place our rafter stock size calculator shows you how long your rafters should be so you ll know what you need in terms of framing lumber dimensional lumber studs and more.

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. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.