Spacing is measured from the center of one joist to the center of the next.
Max span for 2x10 floor joist.
A 2x8 up to 12 feet.
These tables can also be used to determine deck joist span.
One must take into consideration the spacing of the joists and type of wood used.
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.
Span calculator for wood joists and rafters also available for the android os.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
View joist rafter tables.
Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart.
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.
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.
Dead load weight of structure and fixed loads 10 lbs ft 2.
1 ft 0 3048 m.
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.
Dead load is the weight of the structure and any fixed items.
2 grade of douglas fir are indicated below.
2x10 to 15 feet and 2x12 to 18 feet.
True floor joist span calculations can only be made by a structural engineer or contractor.
If you have any questions.
Span entries are listed for 2 6 through 2 12 joists and 12 in 16 in and 24 in.
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.
This chart is for basic reference only.
1 psf lb f ft 2 47 88 n m 2.
The larger the deck the larger the joists.
Also available for the android os.
Live load is weight of furniture wind snow and more.
Maximum floor joist span for no.
Additionally the load that the floor needs to support is also a consideration.
The maximum span for a 2 x 10 floor joist is up to 21 feet depending on several factors.
