Timber Floor Joist Span Tables

These span tables assume installation of at least three joists or rafters that are spaced not more than 24 on center.

Timber floor joist span tables.

Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Joist span table for floor joists floor joist span tables for various sizes and species of wood 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. Span tables use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Straight line interpolation shall be permitted for intermediate spans and design values.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. View joist rafter tables. The calculated spans assume fully supported members properly sheathed and nailed on the top edge of the joist or rafter.

Bci joists are specially constructed i joists with flanges made from strong versa lam laminated veneer lumber with oriented stranded board webs and approved waterproof structural adhesives providing outstanding strength and durability.