Porch Roof Beam Span Table

The smallest beams for patio covers are typically 4 by 6.

Porch roof beam span table.

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. Jan 15 2017 a simple buying guide for beams and rafters that support patio roofs. Includes size and spacing tables for load bearing and links to related articles. If you move up to 4 by 8 you re usually allowed to span up to 10 feet between posts.

For the initial calculation f can be estimated at 1 000. Tables 7 12. The total load is 4 000 pounds. Download a pdf.

The tables below give maximum spans for rafters and beams. Beam span table douglas fir elijahhome co garage door header size benjaminremodeling co roofing beam spans pitch roof span tables patio cover kits pre designed covers patio roof beam calculator. A 4 by 10 can usually span up to 12 feet between posts. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

In the example the beam spans the 10 foot width of the roof. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.

L stands for the span of the beam in feet. 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. In general the maximum span for a 4 by 6 beam is 6 feet between 4 by 4 posts. The figures are based on quality materials.