Floor Joist 4x4 Beam Span Table

A double 2x12 beam can span 12 feet.

Floor joist 4x4 beam span table.

When supporting joists that span 12 feet with no overhang beyond the beam a double ply beam can span in feet a value equal to its depth in inches. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. Also available for the android os.

Table 9 1 in span tables for joists and rafters figure 5 gives a required compression value of 237 psi for a span of 16 feet and bearing length of 1 5 inches. 2x6 if joists are spaced. 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. 2x6 if joists are spaced.

You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Our floor joist span tables are based on loadings given in the newer amended version of bs 6399 1. 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. This means that some values are slightly more conservative than span tables from other sources if those do not include the amended guidance.

A 2 2x10 can span 10 feet and so on. View joist rafter tables. The tables permit a bearing length of up to 3 5 inches but since 1 5 is probably the worst case that you ll encounter for joist or rafter bearing it s a safe value. Design properties 16 floor span and load tables 17 allowable holes 18 roof span and load tables 19 cantilevers 20 21.

True floor joist span calculations can only be made by a structural engineer or contractor. Span tables for domestic floor joists to bs 5268 7 1 note. 2 and better southern pine or douglas fir joist. Dimensional lumber deck beam span chart.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. The numbers in gray indicate the distance between the support posts. Span calculator for wood joists and rafters also available for the android os.