Typical Roof Rafter Spacing

It will support roof loads for most situations and is the standard for most roof applications.

Typical roof rafter spacing.

Stockbyte stockbyte getty images when placing rafters for a tin roof also frequently referred to as corrugated metal or steel it is common to set the distance between rafters based on the size of the roofing panels. This is the distance between rafter centres. In california 16 is by far the most common for residential construction. Since most sheets are 4 x8 typical rafter spacing are 12 16 24.

Use these two tables for roof rafters with a slope greater than 3 in 12. The closer the rafters are to each other the stronger the roof will be. Usually 400 450 or 600mm but any value can be used up to 610mm max are there any brittle finishes e g. There is no standard spacing it depends on what size of rafters you want to use and the span of your shed.

Builders aren t bound by standard rafter spacing measurements. The most common rafter spacing is 24 inches and 5 8 inch plywood is recommended for that. But they do tend to space rafters in one of several industry standard increments typically either 12 16 or 24 inches apart. It is always better to have a large rafter rather than be concerned with a sagging roof.

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 douglas fir or southern pine. In the us they are typically spaced at fractions of the roof sheathing size. Rafter spacing depends on the roofing panel size. For instance 2 grade 2x4s at 16 on center will span just over 9.

For standard shed roof rafter spacing see rafter span chart. The above spans are based on american softwood lumber standard sizes. Plasterboard on the underside of the rafter.