Flat Roof Joist Span

This is the distance between joist centres.

Flat roof joist span. 2 are indicated below. 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. These span tables are the equivalent of other industry standard span tables and are calculated to the same standards. 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.

For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements. Also available for the android os. Size of joists mm clear span c16 joist m clear span c24 joist m 47 x 95 47 x 120 47 x 145 47 x 170 47 x 195 47 x 220 1 77 2 40 2 89 3 38 3 87 4 36 2 04 2 75 3 47 4 20 4 93 5 66 floor joists flat roof joists assumptions at 400mm centers supporting permanent load excluding self weight of joists up to 50kg m2. 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.

This table uses commonly available uk regularised timber depths. Use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size. This span table is to the format and methodology given in bs 5268 7 2. Usually 400 450 or 600mm but any value can be used up to 610mm max 1 2 timber strength class and joist size automatically calculate sizes suitable for supporting the loads below.

For timber floors between homes. Live load is weight of furniture wind snow and more. 1 ft 0 3048 m. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.

Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. These spans were calculated using our flat roof joist calculation engine. The section sizes are based on regularised als or cls timber. Tables 1 and 2 in this chapter are derived from the trada technology ltd.

Dead load weight of structure and fixed loads 15 lbs ft 2. Span tables for solid timber joists.