Roof Deck Span Table

The tables below give maximum spans for rafters and beams.

Roof deck span table.

When supporting joists that span 12 feet with no overhang beyond the beam a double ply beam can span in feet a value equal to its depth in inches. Refer to the deck beam span table below to assist in determining the maximum span of a given beam between posts. Minimum length is limited to 75 of the span length i e for 8 ft. Steel joists and steel deck load tables can facilitate the design of your next project featuring new millennium structural steel buildings systems.

Support spacing 6 ft three inch decking not less than 40 to be 14 ft. A redwood 4x6 beam should span no more than 6 between supporting posts. Obviously the larger the beam the greater the distance it can span between posts. And longer not more than 10 to be less than 10 ft.

Span tables use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Not in excess of l 240 of the span. Load tables are calculated using section properties based on the steel design. A 2 2x10 can span 10 feet and so on.

Joist and rafter span tables. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. The profile contains 4 ribs and is 32 inches wide with male and female edges creating an interlocking side lap when installed. The 3 inch deep ribs make n deck ideal for longer span conditions where b deck falls short.

View joist rafter tables. Dimensional lumber deck beam span chart the numbers in gray indicate the distance between the support posts. A double 2x12 beam can span 12 feet. Not more than 1 to be 4 to 5 ft.

The figures are based on quality materials. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Home building a deck deck beam. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.

In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. Two inch decking not less than 40 to be 14 ft. Type n profiles are 3 inch deep structural roof deck that provide both vertical load and diaphragm shear capacity. Loads shown in the shaded areas are governed by the live load deflection.