Deck Floor Joist Span Tables. Dimensional Lumber Deck Beam Span Chart. Internal Floor Joist Spans for 450 mm and 600 mm Joist Spacing Single Span Joist Spacing 450 mm Joist Spacing 600 mm Size DB mm F5 F7 MGP 10 F5 F7 MGP 10 9035 NS 1000 NS NS NS NS.
Both tables are based on the use of 2 grade lumber. 40 pounds per square foot. These tables can also be used to determine deck joist span.
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 lbsft 2.
The smaller the spacing the longer your joists can span. Placing a layer of 110 mm malthoid dampcourse or proprietary protecti on system on top of the joists will increase the service life of the joist refer Figure 2. For a 40 span on a residential job. Dimensional Lumber Deck Beam Span Chart.
