Shed Roof Rafter Span Calculator

Print full scale rafter cut templates and birdsmouth templates fold template over rafter to mark or cut through.

Shed roof rafter span calculator.

Half building width minus 1 2 ridge thickness. The run for a lean to shed rafter ending into a wall should account for the ridge board nailed into the wall where the tops of the rafters rest into. 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 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. The preview window displays a dimensioned side view of the shed roof. This calculator is to be used as an estimating tool only. Allow for ridge thickness when determining rafter run to outer wall.

Span calculator for wood joists and rafters also available for the android os. Also available for the android os. If you look at the rafter span chart you ll notice that 2x4s can be used for rafters on spans up to 11. 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.

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. See rafter run to outer wall calculator below. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. 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.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. To calculate a shed roof select shed from the roof type dropdown list or click on the corresponding button on the toolbar to calculate a shed roof. Anything beyond that you are looking at using 2x6s for most sheds.