Roof Truss Span Calculator

Is a family owned and operated designer and manufacturer of wooden roof trusses in north central idaho.

Roof truss span calculator.

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. Also available for the android os. While every effort has been made to insure the accuracy of the information presented and special effort has been made to assure that the information reflects the state of the art neither the west coast lumber inspection bureau the american wood council nor its members assume any responsibility for any particular design prepared from this online span calculator. This online truss calculator will determine the all in cost of your truss based on key inputs related to the pitch width and overhang of your roof.

To size joists and rafters use the maximum span tables for southern yellow pine. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. This rafter span calculator is species specific for douglas fir hemlock etc. The shapes and spans shown here represent only a fraction of the millions of designs produced by alpine engineers.

Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. More roof calculators roof truss calculator how to cut rafters. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Span calculator for wood joists and rafters also available for the android os.

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. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads. It will use the current cost of wooden rafters based on the average price found at home improvement stores. 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.

Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters.