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.
Actual size of 2x10 floor joist.
1 ft 0 3048 m.
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.
Actual board sizes in inches nominal size.
It should be noted that limitations on the allowable notching and boring of wood joist are meant to retain the structural and functional integrity of the member.
1 psf lb f ft 2 47 88 n m 2.
Common joist spacings for 2 by 10 joists and other dimensional lumber sizes are 12 16 and 24 inches.
Actual dimensional lumber is cut to a specific length width and depth.
That means a 2x10 is actually 1 1 2 inch in thickness by 9 1 4 inches.
Dead load weight of structure and fixed loads 10 lbs ft 2.
2x4 and 2x6 boards lose 1 2 inch in thickness and 1 2 inch in width before leaving the mill.
2x4s are not actually 2 inches by 4 inches.
When the board is first rough sawn from the log it is a true 2x4 but the drying process and planing of the board reduce it to the finished 1 5x3 5 size.
That means a 2 x 4 board is actually 1 1 2 inches by 3 1 2 inches.
Get free shipping on qualified 2x10 joist hangers or buy online pick up in store today in the building materials department.
1 x 1 3 4 x 3 4 1 x 2 3 4 x 1 1 2 1 x 3.
Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart.
However there is a difference between the nominal size what the lumber is referred to and the actual size.
Get free shipping on qualified 2 in x 10 in pressure treated lumber or buy online pick up in store today in the lumber composites department.
Below is a helpful chart that provides actual notch and hole size limitations for 2x4 2x6 2x8 2x10 and 2x12 joists.