Rafter Sizes For A Pitched Roof

Rafter stock size calculator.

Rafter sizes for a pitched roof.

That means it can span a total length of over 26 for a gable roof. For pitched roofs flat roofs and ceiling joists. Click the button to calculate the stock size needed for this job. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.

The above spans are based on american softwood lumber standard sizes. As aforementioned there is no standard pitch of a roof. This calculator is to be used as an estimating tool only. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

Input the rafter span on the flat eave overhang and pitch of the roof. Again make sure to consult local codes. Input the rafter span on the flat eave overhang and pitch of the roof. You write the pitch assuming a run of 12 inches thus the ratio would describe how much a roof rises for each foot of the run.

Can span up to 13 4. These numbers are for roofs supporting light loads of 20 pounds for square foot. An syp 2 6 rafter at 24 o c. Roof pitch between 30 and 45 degrees with rafter spacing strength class c24 maximum clear span of purlins in metres for roof pitches of between 30 and 45 degrees roof pitch between 30 and 45.

If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. But the most commonly used pitches range between 4 12 and 9 12. It is always better to have a large rafter rather than be concerned with a sagging roof. This calculator is to be used as an estimating tool only.

Area span on the flat. Rafter length using angle v r 2cos a rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch use our online rafter length calculator to quickly compute the length of the shed roof rafter by entering the measurements of overhead length of roof span pitch or angle. An spf roof at the same spacing and lumber size will span 11. Use these two tables for roof rafters with a slope greater than 3 in 12.

How do you calculate the slope of a roof. Rafter span tables use these two tables for roof rafters with a slope of 3 in 12 or less. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof.