Looks like half the allowable beam span is suggested in the chart.
Floor joist dimensional lumber span chart.
Clayton f 8 10 2017 11 31 11 pm reply.
Wood species spacing o c ss grade 1 grade 2 grade 3 grade.
Cam s 6 25 2017 10 41 46 pm reply.
Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size.
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 table is for residential construction only and is meant only for the purposes of initial estimation.
Span calculator for wood joists and rafters also available for the android os.
Also available for the android os.
Floor joist span tables for various sizes and species of wood.