Minimum Roof Pitch For Architectural Shingles

For low slopes as well as any other slope your local building department should be contacted.

Minimum roof pitch for architectural shingles.

A roof slope of 2 12 up to but not including 4 12 is considered as low in residential construction. What slope is considered low slope for shingles. 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. Shingles of all types need to have a slope to function properly.

Therefore the asphalt manufactures base their warranties around the minimum recommended pitch of 4 in 12. 4 12 to 20 12 pitches. Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run. The minimum requirement is 2 12.

For pitches of 2 5 12 up to 4 12 the roof requires double underlayment. You could also opt for a pvc flat roofing membrane. Asphalt shingles installed on a slope below the recommended roof pitch asphalt composition shingles are designed to be installed on roof slopes greater than a 4 in 12 pitch. So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run.

However you can only use this pitch with built up roofing or specialized synthetic roofing. Clay or cement tiles can be used on a wide range of roof pitches. Asphalt shingles should never be applied to roof slopes below 2 12 2 of vertical rise for every 12 of horizontal run or 9 5. Tuesday september 11 2018 manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.

Additional underlayment protection with special application methods are required when asphalt shingles are installed on a low slope roof following the manufacturer s application instructions. What is the minimum pitch slope of an asphalt shingle roof. 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 minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.

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. The 2 12 number is rise over run or two units of vertical for every 12 units horizontal. Asphalt shingles continue to be the most widely installed roof covering option in north america. 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.