Porch Roof Beam Span Table

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

Porch roof beam span table.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. The figures are based on quality materials. If you move up to 4 by 8 you re usually allowed to span up to 10 feet between posts. In general the maximum span for a 4 by 6 beam is 6 feet between 4 by 4 posts.

Download a pdf. For the initial calculation f can be estimated at 1 000. Tables providing size selections for various beam spans and loading combinations for southern pine dimension lumber and southern pine glued laminated timber are available for the following applications. F stands for the beam s fiber strength in bending which depends on the species of wood.

A 4 by 10 can usually span up to 12 feet between posts. Includes size and spacing tables for load bearing and links to related articles. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Tables 7 12.

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. 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. Jan 15 2017 a simple buying guide for beams and rafters that support patio roofs. The total load is 4 000 pounds.

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. In the example the beam spans the 10 foot width of the roof. 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.