Maximum Floor Joist Span

Span entries are listed for 2 6 through 2 12 joists and 12 in 16 in and 24 in.

Maximum floor joist span.

This is the most common as the typical span is 15 feet. The l 480 table with a 40 per square foot live load and a 20 per square foot dead load with a depth of 11 7 8 inches will give you spans according to joint weight. 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 refers to the length of the i joist.

Also available for the android os. Douglas fir larch lumber species no. 2 lumber grade all joists are bridged sample floor joist span table. The spans are based on simple span joists.

With these factors the lightest joist will have a maximum span of 17 feet 8 inches. The maximum span is measured o c. 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. True floor joist span calculations can only be made by a structural engineer or contractor.

Of bearings and is based on uniformly loaded joists. 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. 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.

The table excerpt above is simply a sample and may not be valid for your region. The minimum bearing length is 1 spans values in bold indicate that web stiffeners are required at the osb end panel. 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. Maximum floor joist span for no.

Joist span and spacing is set by your local building code. Live load is weight of furniture wind snow and more. 1 psf lb f ft 2 47 88 n m 2. Dead load weight of structure and fixed loads 10 lbs ft 2.

2 grade of douglas fir are indicated below. Dead load deflection is limited to l 360 and total load deflection is limited to l 240. While most residential construction uses 2x8 joists with 16 inch spacing there are many other factors you need to consider when determining the proper joist span length.