Minimum Roof Pitch Shingled Roof

What is the minimum pitch slope of an asphalt shingle roof.

Minimum roof pitch shingled roof.

The 2 12 number is rise over run or two units of vertical for every 12 units horizontal. The minimum requirement is 2 12. The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run. The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.

Asphalt shingles continue to be the most widely installed roof covering option in north america. This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units. It is important for shingle roofs to function properly and one method of ensuring that this is achieved is to observe the pitch requirements for the shingles. There are some standing seam metal roofing options available from atas and other manufacturers that can be installed on a roof with pitch of 1 12.

Asphalt shingles can only be installed on roof slopes of 2 12 or greater. The minimum pitch is typically 3 12 meaning the roof should rise 3 inches for every 12 inches of horizontal foot. The standard of lower pitch actually ranges between 1 12 to 5 12. That works out to about nine degrees if that works better for you.

The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. The metal roof minimum slope doesn t stray far from other building with different material. So you would need to pick the right option as most regular standing seam metal roofs will require a roof pitch of 2 12 or even 3 12 at a minimum.

However you can only use this pitch with built up roofing or specialized synthetic roofing. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. You could also opt for a pvc flat roofing membrane.