Standard Roof Rafter Spacing

If your local building authority has a rafter spacing code you may not space rafters wider than required by code.

Standard roof rafter spacing.

Rafter and roof joist spacing is only one part of a complex roof design that works together to form a structure that meets building codes and can hold up the weight of the roof and roof load. Spacing of roof framing members depends on the type and thickness of the roof sheathings boads and the regional snow loads. There is no standard spacing it depends on what size of rafters you want to use and the span of your shed. Wider panels allow for greater spacing between rafters.

Rafters must be strong enough to hold the roof sheathing and the shingles. On center as the roof sheathing is span rated for 24 o c. Here in northern wisconsin must roof framing is 24 o c. Rafter spacing is based on the width of the metal roofing panels.

For instance 2 grade 2x4s at 16 on center will span just over 9. Builders aren t bound by standard rafter spacing measurements. A metal roof must also allow for some overlap on each side of the panels which will reduce the effective width of the panel. For standard shed roof rafter spacing see rafter span chart.

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.