Span Flat Roof Joist

Use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size.

Span flat roof joist.

1 enter joist details 1 1 span and joist spacing. Supporting imposed load for access and repair only. 1 psf lb f ft 2 47 88 n m 2. This demo version is fixed at 1m clear span.

Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope. Flat roof joist calculator. Span tables for flat roof joists to bs 5268 7 2 imposed loads of 0 75 kn m for maintenance and snow load are applicable where there is no permanent access no fixed ladder or staircase and most areas where the altitude does not exceed 100 metres refer to bs 6399 3. At least 40mm bearing on supports.

Timber to be covered these span tables do not apply to timber which is fully exposed to the elements. Maximum slop3 10 deg. For pitched roofs flat roofs and ceiling joists. 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.

Span is clear span between supports. Span calculator for wood joists and rafters also available for the android os. 1 ft 0 3048 m. These span tables apply only to flat roof and roof with a slope of up to 10 degrees.

Joist breadth 47mm. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no. Surveyors span tables for designing roof rafters. Also available for the android os.

This is the distance between joist centres. Live load is weight of furniture wind snow and more. Floor joists flat roof joists assumptions at 400mm centers supporting permanent load excluding self weight of joists up to 50kg m2. 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.

Dead load weight of structure and fixed loads 15 lbs ft 2. The full version allows any size. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. 2 are indicated below.