Wood shakes require a minimum roof pitch of 3 12 or greater.
Minimum roof pitch for shingles.
That works out to about nine degrees if that works better for you.
Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater.
What is the minimum pitch slope of an asphalt shingle roof.
Slate and slate type shingles require a minimum roof pitch of 4 12 or greater.
The minimum requirement is 2 12.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Tuesday september 11 2018.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
What is the minimum slope for an asphalt shingle roof.
Shingles of all types need to have a slope to function properly.
However it is regrettable that many installers usually ignore this requirement due to the desire for a quick installation process.
So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run.
Manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.