Floor Joist And Beam Spans

Ceiling joist span use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size.

Floor joist and beam spans.

View size selection tables. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Simply enter the required span to see a range of results that will work. Since the example house we are designing for is 12 feet wide we need to find in the floor joist span table a joist size and centering that can span 12 or wider.

Beam and joist span tables built up wood floor beams supporting one floor in a house maximum spans for uniformly distributed loads species and grade supported built up beam size joist length 3 2x8 4 2x8 3 2x10 4 2x10 3 2x12 4 2x12 8 9 8 11 2 11 10 13 8 13 8 15 10 10 8 8 10 0. Spans of timber joists in suspended timber ground floors. Surveyors and structural engineers use data from tables below to help calculate the size of timbers necessary to give adequate support to timber floors. See the image below for an example of joists spaced 16 on center 16 o c.

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. Our floor joist beam can span a maximum of 13. The ontario building code spans for joists rafters and beams 9 23 4 2. 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 2400 mm and 3 6 kn load per metre width of floor for spans less than 2400 mm to ensure that very small joist sizes do not result from the calculations for smaller spans.

Floor joist span tables for surveyors floor construction. Simplified span tables for southern pine lumber and glued laminated timber glulam headers beams and girders. The floor joist spacing is the distance between the centers of any two installed joists. Try our interactive span checker to find the posi joist suitable for your project.

So we now have adequately sized floor joists and an adequately sized floor joist beam for our 24 x 13 house. In the table above the widest floor beam span for 12 of supported floor joists is 14 7 if using a 5 ply 2 x 12. 2 spans for floor joists that are not selected from tables a 1 and a 2 and that. True floor joist span calculations can only be made by a structural engineer or contractor.

View joist rafter tables.