These 46 tables are based upon design values for visually graded southern pine dimension lumber that became effective june 1 2013.
Roof rafter span fir 3x8.
Tables listing maximum spans for southern pine joists and rafters are detailed below.
Let s consider a basic gable wood roof framing design.
Span calculator for wood joists and rafters also available for the android os.
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.
Span calculator for wood joists and rafters available for the iphone.
Here we have a wood framed gable roof.
1 psf lb f ft 2 47 88 n m 2.
For each application a pdf download is available.
Span calculator for wood joists and rafters also available for the android os.
More roof calculators roof truss calculator how to cut rafters.
Live load is weight of furniture wind snow and more.
To size joists and rafters use the maximum span tables for southern yellow pine.
Floor beam span tables of residential structural design we will now look at roof rafter and beam design.
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.
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.
1 ft 0 3048 m.
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.
Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.
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.
2 are indicated below.
The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.
This is based upon the span of the rafter horizontal span not total rafter length live and dead loads.
This rafter span calculator is species specific for douglas fir hemlock etc.