Flat Roof Joists Span

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

Flat roof joists span. Span calculator for wood joists and rafters also available for the android os. Span ft 1 5 2 0 2 5 3 0 3 5 2 30 22 18 15 13 4 59 44 36 30 25 6 89 67 53 44 38 8 119 89 71 59 51 10 148 111. 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. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

This is the distance between joist centres. Span tables for joists and rafters 3 american wood council table 9 1 required compression perpendicular to grain design values f c in pounds per square inch for simple span joists and rafters with uniform load. This demo version is fixed at 1m clear span. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

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. View joist rafter tables. Spans for joists greater than 20 feet that are parallel to the rafters require a 12 inch joist spacing when using 2 inch by 10 inch 2 douglas and hemlock fir or southern pine or 16 inch spacing when using 2 inch by 10 inch 2. The full version allows any size.

1 psf lb f ft 2 47 88 n m 2. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no. Roof truss span chart.

Flat roof joist calculator. In these cases 2 inch by 10 inch lumber is often used for ceiling joists although trusses may be more practical. 1 ft 0 3048 m. Also available for the android os.

Dead load weight of structure and fixed loads 15 lbs ft 2. Live load is weight of furniture wind snow and more. Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. 1 enter joist details 1 1 span and joist spacing.

Trusses with an asterisk that exceed 14 in height may be. 2 are indicated below.