Hem fir 2 joists with a live dead load of 40 10 psf.
Floor span for 2x12.
3 due to fewer knots and defects in the grain of the wood.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
Live load is weight of furniture wind snow and more.
Floor joist span tables for various sizes and species of wood.
Also available for the android os.
3 allow shorter spans.
This span table excerpt shows two possible sizes of built up floor beams 2 x 10 and 2 x 12.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
The full table shows more lumber sizes.
1 ft 0 3048 m.
See our complete chart of floor joist size span and spacing requirements before you build.
The numbers in gray indicate the distance between the support posts.
This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction.
Joist span table use these tables to determine floor joist spans based on grade of lumber size of joist floor joist spacing and a live load of 30 lbs ft 2 or 40 lbs ft 2 these tables can also be used to determine deck joist span.
Maximum floor joist span for no.
A double 2x12 beam can span 12 feet.
Three other grades no.
We ve included 2x6 2x8 2x10 and 2x12 joist spans and more.
It also shows the maximum that the beam can span for various numbers of such pieces of lumber built together this is indicated by 3 ply 4 ply and 5 ply.
Boards cut and graded as structural select allow the longest spans.
2 grade of douglas fir are indicated below.
Span calculator for wood joists and rafters also available for the android os.
Dimensional lumber deck beam span chart.
Spans in this table were derived from the irc table r502 3 1 2 design criteria.
1 psf lb f ft 2 47 88 n m 2.
Floor joists support structural load and require lumber species capable of supporting those loads.
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.
True floor joist span calculations can only be made by a structural engineer or contractor.