Maximum Span Of Floor Joists

1 psf lb f ft 2 47 88 n m 2.

Maximum span of floor joists. 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. Solid timber joist sizes are provided in the bs 8103 3 span tables. Spacing is measured from the center of one joist to the center of the next.

Other span tables are based on the guidance given in bs 5268 7 1 which is a uniformly distributed load of 1 5kn m for spans greater than. The icc replaced the cantilever portion of the table in the 2018 irc with a maximum overhang length making the table similar to that in dca6. True floor joist span calculations can only be made by a structural engineer or contractor.

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. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. 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. Also available for the android os. Live load is weight of furniture wind snow and more.

The cantilever portion of the 2015 irc joist span table is awkward to use. Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart. 2 grade of douglas fir are indicated below.

Floor joist span tables for various sizes and species of wood. Maximum floor joist span for no. 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.