Pitched Roof Rafter Spacing

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.

Pitched roof rafter spacing.

Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches. For pitched roofs flat roofs and ceiling joists. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. So the space between rafters can be greater without reducing the maximum span.

If your local building authority has a rafter spacing code you may not space rafters wider than required by code. The same concept holds true for roof trusses. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.

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. Surveyors span tables for designing roof rafters. 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.