Search results
7 paź 2023 · According to IRC 2021, a 2×10 with 16-inch spacing can span up to 18′-9″ as floor joists, more than 26′ as rafters and ceiling joists,4′-3″ as beams, and 7′ as headers without providing additional support. These values apply to Southern Pine Species.
A #2-2×10 joist can span between 11’-5” and 18’-0”, as a rafter between 13’-9” and 21’-7”, and as a beam 3’-6” and 13’-0” or more. The span depends on spacing, lumber species, and grade, and for a beam, the lamination thickness, as well as numerous other factors.
Find local businesses, view maps and get driving directions in Google Maps.
Step 2 Span Table: Select the appropriate table in Span Tables for Joists and Rafters. The Table of contents indicates that Table F-2 matches these loading conditions. Using Table F-2 (Figure #3), check each lumber size to see if a 16-inch spacing will permit a span of 15 feet 1 inch.
Joist span table - use these span tables to determine maximum spans based on the species and grade of lumber, the size of the floor joists, the spacing of the floor joists, and either of these two common design scenarios: Live load of 30 PSF / a dead load of 20 PSF / and a deflection limit of L/360.
Use the span tables in the links below to determine the maximum allowable lengths of joists and rafters. These tables provide maximum spans for the #2 grades of four common species of lumber (Southern Pine, Douglas Fir, Hem-fir, and Spruce-pine-fir (SPF).
Span Options Calculator for Wood Joists and Rafters. Performs calculations for ALL species and grades of commercially available softwood and hardwood lumber as found in the NDS 2018 Supplement. Joists and rafter spans for common loading conditions can be determined.
