Porch Roof Beam Span Table

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

Porch roof beam span table.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. The total load is 4 000 pounds. Includes size and spacing tables for load bearing and links to related articles. In general the maximum span for a 4 by 6 beam is 6 feet between 4 by 4 posts.

Tables 7 12. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Fill in the parts of the formula that are already known. The figures are based on quality materials.

For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. A 4 by 10 can usually span up to 12 feet between posts. Jan 15 2017 a simple buying guide for beams and rafters that support patio roofs. L stands for the span of the beam in feet.

In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. 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. If you move up to 4 by 8 you re usually allowed to span up to 10 feet between posts. 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.

The tables below give maximum spans for rafters and beams. F stands for the beam s fiber strength in bending which depends on the species of wood. Download a pdf. For the initial calculation f can be estimated at 1 000.