Maximum Span For Double 2x8 Floor Joists

While every effort has been made to insure the accuracy of the information presented and special effort has been made to assure that the information reflects the state of the art neither the west coast lumber inspection bureau the american wood council nor its members assume any responsibility for any particular design prepared from this online span calculator.

Maximum span for double 2x8 floor joists. Joist span and spacing is set by your local building code. The larger the deck the larger the joists. 2x10 to 15 feet and 2x12 to 18 feet. A 2x8 up to 12 feet.

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. True floor joist span calculations can only be made by a structural engineer or contractor. 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. Is there a table or a way of figuring how far 2 x 8 s doubled up can span.

A 2 2x10 can span 10 feet and so on. Dimensional lumber deck beam span chart. Span calculator for wood joists and rafters also available for the android os. When building a house or even a deck it is important to confirm you have the correct joist sizes spans and spacing before you get started.

Code requirements minimum code requirements for standard construction projects will require the l 360 table with a 40 per square foot live load and a 10 per square foot dead load. 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. Floor joist span tables for various sizes and species of wood. Also available for the android os.

Dead load weight of structure and fixed loads 10 lbs ft 2. The numbers in gray indicate the distance between the support posts. A contractor is proposing to use double 2x8 s to span 15 4 to avoid having to provide an intermediate bearing wall. A double 2x12 beam can span 12 feet.

1 psf lb f ft 2 47 88 n m 2. 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. Maximum floor joist span for no. 2 grade of douglas fir are indicated below.

The heaviest joist along with the above factors will span a maximum of 23 feet 8 inches.