Roof Rafter Spacing

Use these two tables for roof rafters with a slope greater than 3 in 12.

Roof rafter spacing.

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. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. The above spans are based on american softwood lumber standard sizes. 2 4 rafters can span up to 7.

Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. It is always better to have a large rafter rather than be concerned with a sagging roof. So the space between rafters can be greater without reducing the maximum span. There is no standard spacing it depends on what size of rafters you want to use and the span of your shed.

Rafter span tables use these two tables for roof rafters with a slope of 3 in 12 or less. If you get premium kiln dried lumber then you could span 10 5 with the same size of lumber and rafter spacing. The same concept holds true for roof trusses. Rafter spacing is based on the width of the metal roofing panels.

A metal roof must also allow for some overlap on each side of the panels which will reduce the effective width of the panel. Wider panels allow for greater spacing between rafters. Rafter spacing rafters must be strong enough to hold the roof sheathing and the shingles. Since most sheets are 4 x8 typical rafter spacing are 12 16 24.

Most roof framing is 24 on center and you can still build sheds up to 14 with 2 4 rafters at 24 on center. For light load roofs 24 o c. If your local building authority has a rafter spacing code you may not space rafters wider than required by code. For standard shed roof rafter spacing see rafter span chart.

Spacing your 2 4 shed rafters at 24 on center limits the width of your roof. For instance 2 grade 2x4s at 16 on center will span just over 9. For heavy loads 2x4s can span up to 5. In california 16 is by far the most common for residential construction.

Typical rafter spacing codes will specify a minimum spacing of 16 inches 19 2 inches or 24 inches.