Porch Roof Beam Span Chart

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Porch roof beam span chart.

This tells you the size of the beam needed to support the porch s roof. In the example d calculates to 7 75. This post may contain affiliate links. Window door garage door headers supporting roof wall floor loads.

This means the example porch would need a 6 inch by 8 inch beam. Window door garage door headers supporting roof loads only. Calculate the initial value for d then round it up to the nearest inch. Lumber species southern pine douglas fir douglas fir larch hemlock fir spruce pine fir redwood western cedar ponderosa pine red pine.

Beam span calculator for help simply click on the beside the section you need help with watch this tutorial video. If you move up to 4 by 8 you re usually allowed to span up to 10 feet between posts. A 4 by 10 can usually span up to 12 feet between posts. The smallest beams for patio covers are typically 4 by 6.

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