What Size Lumber For Roof Rafters

Once all of these inputs have been entered into the calculator you will see that the appropriate rafter width is 120 33 inches.

What size lumber for roof rafters.

This calculator helps you make the rafters of the suitable sizes required for your roofing. The lengths and sizes of joists vary depending on the species and quality of the lumber used. Anything beyond that you are looking at using 2x6s for most sheds. 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.

For roofs that will experience heavy snow or wind and will span the same distance use 2 6 rafters. This rafter span calculator is species specific for douglas fir hemlock etc. Rafter is a sloping beam usually wood that supports a pitched roof. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.

For additional species of lumber check out the rafter span calculator from the american wood council website. To size joists and rafters use the maximum span tables for southern yellow pine. 1 psf lb f ft 2 47 88 n m 2. Rafter and joist span faq.

Just enter the dimensions of the roof rise and run to get started. 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. You can use either 2 6 or 2 4 rafters for roofs with a 3 12 pitch or greater but it depends on the overall size of your shed. Use these two tables for roof rafters with a slope greater than 3 in 12.

Live load is weight of furniture wind snow and more. Trying to find what size lumber to use. Dead load weight of structure and fixed loads 15 lbs ft 2. Here the wall thickness is 240 57 inches.

1 ft 0 3048 m. The above spans are based on american softwood lumber standard sizes. 2 are indicated below. More roof calculators roof truss calculator.

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. In addition using the rafters diagram you can see the precise dimensions of the roof rafter including length from every possible angle. For roofs that won t experience heavy snow loads a gable roof can span up to 22 with 2 4 rafters. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads.

Use these two tables for roof rafters with a slope of 3 in 12 or less. 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.