Roofing Table Rafter Span

The tables below give maximum spans for rafters and beams.

Roofing table rafter span.

To size joists and rafters use the maximum span tables for southern yellow pine. In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot. This rafter span calculator is species specific for douglas fir hemlock etc. Rafter span tables for surveyors roof construction surveyors span tables for designing roof rafters for pitched roofs flat roofs and ceiling joists 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.

Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall. For roof live loads less than 20 pounds per square foot psf rafter spans and required e values tabulated for 20 psf shall be permitted to be adjusted in accordance with the fol lowing table. These 46 tables are based upon design values for visually graded southern pine dimension lumber that became effective june 1 2013. This is based upon the span of the rafter horizontal span not total rafter length live and dead loads.

For each application a pdf download is available. The loads are based on adjusted roof snow loads from the governing building code. 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. For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.

Tables listing maximum spans for southern pine joists and rafters are detailed below. Maximum rafter spans for a patio roof. So this table could accommodate a house with a total rafter span or house width of 32 feet.