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.
Post and beam roof span tables.
The figures are based on quality materials.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
A 2 2x10 can span 10 feet and so on.
Continuing on from part 3.
This span table excerpt shows two possible sizes of built up floor beams 2 x 10 and 2 x 12.
Let s consider a basic gable wood roof framing design.
Patio roof maximum beam rafter spans.
Dimensional lumber deck beam span chart.
Beams of more than one ply must be fastened together with either nails or bolts.
Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.
View joist rafter tables.
In other words the maximum distance it can cover without support from posts.
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.
You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.
Here we have a wood framed gable roof.
The image below shows a cross section of our simple 12 x 13 house from the joist span tables section of this tutorial.
Numbers in blue are joist spans beam to beam or house to beam.
The full table shows more lumber sizes.
This table is simply a sample and may not be valid for your region.
According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2.
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.
On longer spans the beam may require much more bearing space as indicated by this table.
It also shows the maximum that the beam can span.
For lesser grades spans should be shorter.
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 tables below give maximum spans for rafters and beams.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
Sample floor beam span table.
Keep in mind that these are maximums in other words shortening spans slightly will result in a more solid structure.
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.
A double 2x12 beam can span 12 feet.
