Beams of more than one ply must be fastened together with either nails or bolts.
Porch roof header span table.
According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2.
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.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
For a porch roof the beam needs to be sized according to the maximum snow loads in your area and you must know enough about the porch design to determine how the load will be distributed and over what distance the beam will carry the load.
All other data is available on page 121 of the 2012 international residential code.
Window door garage door headers supporting roof loads only.
On longer spans the beam may require much more bearing space as indicated by this table.
The tables below give maximum spans for rafters and beams.
Includes span tables for all load bearing locations and the number of jack studs.
The numbers in gray indicate the distance between the support posts.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
The figures are based on quality materials.
Anything 5 and above we always at least double cripple.
Span charts and 2012 irc building codes for girders and headers.
View joist rafter tables.
For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
A double 2x12 beam can span 12 feet.
In the example the beam spans the 10 foot width of the roof.
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.
The total load is 4 000 pounds.
These charts are for 30 pound per square foot snow load on the roof.
In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size.
Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope.
