Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
Minimum roof pitch for felt shingles.
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 asphalt shingle manufactures recommend that you install asphalt shingles on a recommended minimum of 4 in 12 or greater however most manufactures will warrant their shingles down to a 2 in 12 pitch if the recommended installation method is used.
The minimum requirement is 2 12.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
For the rest of the roof slope the felt underlayment must be installed with a 19 inch top lap and a 12 inch side lap providing double coverage of the felt layer.
Roofing material or system.
In 12 0 25 in 12 1 19 built up roof coal tar pitch.
The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.
Using felt tiles is the next step up in quality.
All asphalt shingle roofs with a pitch of 4 12 or more have an underlayment of 15 lb.
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.
What is the minimum pitch slope of an asphalt shingle roof.
Minimum required slope x in 12 minimum required slope degrees asphalt shingles.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
Minimum required roof slope for roofing materials.
Asphalt felt paper that is tacked to the roof sheathing.
Shingles of all types need to have a slope to function properly.
9 46 built up roof asphalt.
But shingle roofing is not watertight in the sense that standing water or wind driven water on a low slope roof can work its way up between the laps which is the reason for the minimum 2 12 slope.
Asphalt shingle manufacturers will warrant shingles installed on roof slopes as low as 2 12 when these special installation procedures are followed.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
That works out to about nine degrees if that works better for you.
Installation on roof slopes below a 2 in 12 pitch is not recommended at all.
For roof slopes of four units vertical in 12 units horizontal 33 percent slope or greater underlayment shall be a minimum of one layer of underlayment felt applied shingle fashion parallel to and starting from the eaves and lapped 2 inches 51 mm fastened only as necessary to hold in place.
The shingles overlap each other by about 150 mm at the ridge a capping piece is used.
Asphalt shingles require a minimum roof pitch of 2 12 or greater.
18 43 asphalt shingles with special underlayment requirements 2 in 12.
Let us recap on the minimum roof pitch required for each type of roofing material.
Felt tiles or roofing shingles.
