The maximum span distance for 12 inch spacing is greater by as much as 30 percent compared to 24 inch spacing.
Maximum span for 2x10 floor joist.
The numbers in gray indicate the distance between the support posts.
1 psf lb f ft 2 47 88 n m 2.
Floor joist table joist size joist spacing maximum span.
A 2 2x10 can span 10 feet and so on.
Dead load is the weight of the structure and any fixed items.
2 2x10 o i 6 2 2x4 2 2x4 2 2x6 2 2x6 2 2x6 2 2x8 2 2x8 2 2x10 2 2x10 s.
Span entries are listed for 2 6 through 2 12 joists and 12 in 16 in and 24 in.
A 2x8 up to 12 feet.
Dimensional lumber deck beam span chart.
Also available for the android os.
Maximum floor joist span for no.
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.
Our joist span charts are for wood joists with a maximum dead load of 10 pounds per square foot and a live load of 40 pounds per square foot.
If you have any questions.
A double 2x12 beam can span 12 feet.
For example in the joist span table below the highlighted cell shows that 2 x 8 southern yellow pine joists that have a grade of 2 and are spaced 24 apart can have a maximum span of 10 feet 3 inches 10 3 if designing for a live load of 40 lbs ft 2.
Live load is weight of furniture wind snow and more.
True floor joist span calculations can only be made by a structural engineer or contractor.
Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart.
Span calculator for wood joists and rafters also available for the android os.
2 grade of douglas fir are indicated below.
The larger the deck the larger the joists.
Dead load weight of structure and fixed loads 10 lbs ft 2.
Live load represents the weight of furniture snow etc.
Spacing is measured from the center of one joist to the center of the next.
In typical deck construction with a ledger on one side of the joist and beam on the other the size of the joists is driven by the size of the deck and based on the general maximum spans mentioned above.
These tables can also be used to determine deck joist span.
This chart is for basic reference only.
The illustrations one for cantilever joists and one for flush rim beam hung joists point out where joist span measurements are taken from the saddle of the ledger mounted joist hanger to the center of a dropped beam or saddle of the.
Spans in this table were derived from the irc table r502 3 1 2 design criteria.
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.
