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.
Maximum span for 2x10 floor joist.
2x10 to 15 feet and 2x12 to 18 feet.
The maximum span distance for 12 inch spacing is greater by as much as 30 percent compared to 24 inch spacing.
Dead load is the weight of the structure and any fixed items.
A double 2x12 beam can span 12 feet.
Floor joist table joist size joist spacing maximum span.
1 psf lb f ft 2 47 88 n m 2.
2 2x10 o i 6 2 2x4 2 2x4 2 2x6 2 2x6 2 2x6 2 2x8 2 2x8 2 2x10 2 2x10 s.
The larger the deck the larger the joists.
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.
Maximum floor joist span for no.
This chart is for basic reference only.
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.
Dead load weight of structure and fixed loads 10 lbs ft 2.
A 2x8 up to 12 feet.
Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart.
Live load represents the weight of furniture snow etc.
1 ft 0 3048 m.
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.
True floor joist span calculations can only be made by a structural engineer or contractor.
These tables can also be used to determine deck joist span.
Span calculator for wood joists and rafters also available for the android os.
If you have any questions.
Dimensional lumber deck beam span chart.
Span entries are listed for 2 6 through 2 12 joists and 12 in 16 in and 24 in.
2 grade of douglas fir are indicated below.
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.
Also available for the android os.
A 2 2x10 can span 10 feet and so on.
