Post And Beam Roof Span Tables

Here we have a wood framed gable roof.

Post and beam roof span tables.

The tables below give maximum spans for rafters and beams. According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. View joist rafter tables.

The tables permit a bearing length of up to 3 5 inches but since 1 5 is probably the worst case that you ll encounter for joist or rafter bearing it s a safe value. Sample floor beam span table. This table is simply a sample and may not be valid for your region. It also shows the maximum that the beam can span.

Anything 5 and above we always at least double cripple. Patio roof maximum beam rafter spans. Dimensional lumber deck beam span chart. This span table excerpt shows two possible sizes of built up floor beams 2 x 10 and 2 x 12.

There are several beam span tables for all the species of wood. Pergola beam span calculator bestpergoladesign post 7970212113 pergola main beams span building construction diy chatroom pergola main beams span building construction diy chatroom measuring pergola dimensions learn the standard patio roof maximum beam rafter spans beams sukkah and sukkot at baldwin outdoor comfort the specialists patio roof. Let s consider a basic gable wood roof framing design. Allowable spans vary according to wood species and the loads that the beam will bear such as snow loads or the dead loads of construction materials.

Floor beam span tables of residential structural design we will now look at roof rafter and beam design. The numbers in gray indicate the distance between the support posts. The full table shows more lumber sizes. Table 9 1 in span tables for joists and rafters figure 5 gives a required compression value of 237 psi for a span of 16 feet and bearing length of 1 5 inches.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Continuing on from part 3. A double 2x12 beam can span 12 feet. For lesser grades spans should be shorter.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. On longer spans the beam may require much more bearing space as indicated by this table. The determining factor of post spacing is the allowable span of your beams. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

Keep in mind that these are maximums in other words shortening spans slightly will result in a more solid structure. Beams of more than one ply must be fastened together with either nails or bolts. In other words the maximum distance it can cover without support from posts. The figures are based on quality materials.