Let us recap on the minimum roof pitch required for each type of roofing material.
Minimum roof pitch for felt shingles.
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.
Asphalt felt paper that is tacked to the roof sheathing.
Metal roof shingles require a minimum roof pitch of 3 12 or greater.
Asphalt shingles require a minimum roof pitch of 2 12 or greater.
All asphalt shingle roofs with a pitch of 4 12 or more have an underlayment of 15 lb.
What is the minimum pitch slope of an asphalt shingle roof.
Rough cost m 2.
18 43 asphalt shingles with special underlayment requirements 2 in 12.
Installation on roof slopes below a 2 in 12 pitch is not recommended at all.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
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.
The shingles overlap each other by about 150 mm at the ridge a capping piece is used.
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.
Roofing shingles are laid starting at the bottom of the roof.
That works out to about nine degrees if that works better for you.
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.
9 46 built up roof asphalt.
Asphalt shingle manufacturers will warrant shingles installed on roof slopes as low as 2 12 when these special installation procedures are followed.
Roofing material or system.
Shingles of all types need to have a slope to function properly.
The recommended minimum roof pitch for shingles is 2 12 or simply two units of vertical rise to every twelve units of horizontal span.
In 12 0 25 in 12 1 19 built up roof coal tar pitch.
Using felt tiles is the next step up in quality.
Felt tiles or roofing shingles.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
The minimum requirement is 2 12.
Minimum required slope x in 12 minimum required slope degrees asphalt shingles.
