Lean To Roof Rafter Span Calculator

Input the rafter span on the flat eave overhang and pitch of the roof.

Lean to roof rafter span calculator.

Rafter stock size calculator. An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry. Half building width minus 1 2 ridge thickness. 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.

See rafter run to outer wall calculator below. Also available for the android os. Click the button to calculate the stock size needed for this job. 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.

For more information see our disclosures here. This calculator is to be used as an estimating tool only. 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. This calculator helps you make the rafters of the suitable sizes required for your roofing.

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. For a gothic style the rafters must equal the span 60 while an elizabethan style requires the rafters to be longer than the span. In snowy areas your roof should be at least 10 12 40 to allow snow to shed while the safest roof pitch in very windy areas is between 4 12 6 12 18 5 26 5. In other words if there is a 1 1 2 ridge board nailed into the wall and the width of the lean to is 96 then the run will be 94 1 2 96 1 1 2 94 1 2.

Area span on the flat. 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. Allow for ridge thickness when determining rafter run to outer wall. Print full scale rafter plumb cut templates and birdsmouth templates fold template over rafter to mark or cut through.

Span calculator for wood joists and rafters also available for the android os. Slope the slope of a roof is represented as x 12 where x is the number of inches in rise for every 12 inches of run this is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares. Roof pitch calculator results explained. Patio roof maximum beam rafter spans.

Enter this measurement into the calculator and select a roof pitch and the length of the rafter will automatically returned along with the rise.