Flat Roof Joist Span Chart

This is the distance between joist centres.

Flat roof joist span chart. 1 enter joist details 1 1 span and joist spacing. Flat roof joist calculator. Maximum clear span of flat roof joists in metres for sc3 timber spacing between joists size of roof joist 400mm 450mm 600mm 47 x 97 1 84 1 81 1 74 47 x 120 2 43 2 39 2 27 47 x 145 3 08 3 02 2 87 47 x 170 3 75 3 67 3 42 47 x 195 4 41 4 31 3 92 47 x 220 5 04 4 85 4 41 75 x 170 4 50 4 38 3 99. Timber to be covered these span tables do not apply to timber which is fully exposed to the elements.

Usually 400 450 or 600mm but any value can be used up to 610mm max. This demo version is fixed at 1m clear span. Also available for the android os. The full version allows any size.

Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size. Use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. Notches are not to exceed 0 125 of the depth of the joist and are to be located between 0 07 and 0 25 of the span from the support. Roof rafter span use this table to determine the maximum lengths of roof rafters.