Rafter Span Roof Truss Span Tables

So this table could accommodate a house with a total rafter span or house width of 32 feet.

Rafter span roof truss span tables.

Span calculator for wood joists and rafters also available for the android os. Total load psf duration factor live load psf roof type 55 1 15 40 snow shingle 55 1 15 30 snow tile 47 1 15 30 snow shingle 40 1 15 20. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters. This rafter span calculator is species specific for douglas fir hemlock etc.

To size joists and rafters use the maximum span tables for southern yellow pine. Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall. Rafter spans for southern yellow pine douglas fir and eastern spruce.

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. Roof truss cost member design of a 22m span steel roof truss structville roof trusses design framing construction pryda new zealand floor joist span table roof trusses flooring pier and beam the complete guide to roof trusses design cost framing more roof trusses design framing construction pryda new zealand. For pitched roofs flat roofs and ceiling joists. Also available for the android os.

The calculated spans assume fully supported members properly sheathed and nailed on the top edge of the joist or rafter. The shapes and spans shown here represent only a fraction of the millions of designs processed by alpine engineers. Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. Surveyors span tables for designing roof rafters.

View joist rafter tables. The spans in this table are based on a maximum supported rafter span of 16 feet where the supported span is the total horizontal distance spanned by the roof rafters divided in half not the diagonal distance or the length of the rafter. Straight line interpolation shall be permitted for intermediate spans and design values. Surveyors and structural engineers utilise data from tables below to help calculate the correct size strength and centres of roof timbers for the required spans and loadings.

Use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads.