Porch Roof Beam Span Table

For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

Porch roof beam span table.

Tables 7 12. 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. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. In general the maximum span for a 4 by 6 beam is 6 feet between 4 by 4 posts.

The tables below give maximum spans for rafters and beams. L stands for the span of the beam in feet. The total load is 4 000 pounds. 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. In the example the beam spans the 10 foot width of the roof. A 4 by 10 can usually span up to 12 feet between posts. 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.

Download a pdf. 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. The figures are based on quality materials.

Fill in the parts of the formula that are already known. For the initial calculation f can be estimated at 1 000. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. F stands for the beam s fiber strength in bending which depends on the species of wood.