The figures are based on quality materials.
Roof beam span tables canada.
Tables in the span book and the national building code were both generated by the canadian wood council.
Loading conditions are detailed below.
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.
For each application a pdf download is available.
Anything 5 and above we always at least double cripple.
The canadian wood council s beam calculator has been developed for the purpose of information only.
The span book is a supplement to the wood joist rafter and beam spans found in the national building code of canada.
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.
Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run.
The tables below give maximum spans for rafters and beams.
Refer to sfpa s publication southern pine headers beams download in publications that includes all size selection and allowable load tables.
Tables a 1 to a 16 cover only the most com mon configurations.
Also see assumptions for table development.
According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2.
Keep in mind that these are maximums in other words shortening spans slightly will result in a more solid structure.
A double 2x12 beam can span 12 feet.
Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch.
Also available for the android os.
Beam and joist span tables built up wood floor beams supporting one floor in a house maximum spans for uniformly distributed loads species and grade supported built up beam size joist length 3 2x8 4 2x8 3 2x10 4 2x10 3 2x12 4 2x12 8 9 8 11 2 11 10 13 8 13 8 15 10 10 8 8 10 0 10 7 12 2 12 3 14 2.
The national building code references the span book as follows.
Although all possible efforts have been made to ensure that the information from this tool is accurate the cwc cannot guarantee the completeness accuracy or exactness of the information.
You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.
Span calculator for wood joists and rafters also available for the android os.
A 2 2x10 can span 10 feet and so on.
