Wood Roof Beam Span Table

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.

Wood roof beam span table.

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. Also available for the android os. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Our floor joist span tables are based on loadings given in the newer amended version of bs 6399 1.

For lesser grades spans should be shorter. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. On longer spans the beam may require much more bearing space as indicated by this table. Continuing on from part 3.

Raised wood floor foundations. The tables below give maximum spans for rafters and beams. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. View joist rafter tables.

According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2. Let s consider a basic gable wood roof framing design. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. 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.

This means that some values are slightly more conservative than span tables from other sources if those do not include the amended guidance. Beams of more than one ply must be fastened together with either nails or bolts. Span calculator for wood joists and rafters also available for the android os. Span tables for jois ts and rafters american wood council 4 span tables for joists and rafters american wood council design criteria.

The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial. Anything 5 and above we always at least double cripple. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Deflection for 30 psf live load.

Keep in mind that these are maximums in other words shortening spans slightly will result in a more solid structure. Tables 13 14. The figures are based on quality materials. Span tables for domestic floor joists to bs 5268 7 1 note.