Lumber Size For Roof Rafters

Live load 20 lbs ft 2 956 n m 2.

Lumber size for roof rafters.

Live load is weight of furniture wind snow and more. To size joists and rafters use the maximum span tables for southern yellow pine. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads. Spf 2 6 rafters can span 8.

Click the button to calculate the stock size needed for this job. Trying to find what size lumber to use. Dead load weight of structure and fixed loads 15 lbs ft 2. Home improvement stores do not sell pine boards longer than 20 feet.

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. If you move the rafters closer together at 16 o c then your syp rafters will span 11 and spf up to 10. 2 are indicated below. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.

1 psf lb f ft 2 47 88 n m 2. This rafter span calculator is species specific for douglas fir hemlock etc. 1 in 25 4 mm. Input the rafter span on the flat eave overhang and pitch of the roof.

More roof calculators roof truss calculator. Rafters longer than 20 feet. The lengths and sizes of joists vary depending on the species and quality of the lumber used. 1 ft 0 3048 m.

Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no. Just enter the dimensions of the roof rise and run to get started. Lumber size width 2x8 2x10 or 2x12 boards will be used to estimate cost of each rafter as well as total cost excluding local sales tax. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center.

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 calculator is to be used as an estimating tool only. Rafter and joist span faq.