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.
Roof rafter span fir 3x8.
More roof calculators roof truss calculator how to cut rafters.
1 psf lb f ft 2 47 88 n m 2.
Live load is weight of furniture wind snow and more.
This rafter span calculator is species specific for douglas fir hemlock etc.
To size joists and rafters use the maximum span tables for southern yellow pine.
2 are indicated below.
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.
Span calculator for wood joists and rafters also available for the android os.
For each application a pdf download is available.
Span calculator for wood joists and rafters available for the iphone.
These 46 tables are based upon design values for visually graded southern pine dimension lumber that became effective june 1 2013.
Tables listing maximum spans for southern pine joists and rafters are detailed below.
Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope.
Also available for the android os.
For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.
Continuing on from part 3.
Span calculator for wood joists and rafters also available for the android os.
Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
Let s consider a basic gable wood roof framing design.
1 ft 0 3048 m.
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.
Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.
Here we have a wood framed gable roof.