Min Asphalt Shingle Roof Slope

In case a slope greater than this is necessary then a double underlayment application must be used as per the requirements of the international building code.

Min asphalt shingle roof slope.

This number corresponds to the number of inches of rise in a 12 foot run. Minimum required roof slope for roofing materials. Minimum pitch for corrugated metal roof. 9 46 built up roof asphalt.

Also if asphalt shingles are installed on a roof slope of 2 12 to 4 12 it shall be provided with a double underlayment application. Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work. According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal. 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.

The minimum requirement is 2 12. So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run. In 12 0 25 in 12 1 19 built up roof coal tar pitch. The minimum slope for an asphalt shingle roof is 2 12.

The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. Shingles of all types need to have a slope to function properly. Installation on roof slopes below a 2 in 12 pitch is not recommended at all. 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. The roof pitch between 2 12 and 4 12 is considered as a low pitch roof so shingles can be installed in the roof slope between 2 12 and 4 12. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. 18 43 asphalt shingles with special underlayment requirements 2 in 12.

Minimum required slope x in 12 minimum required slope degrees asphalt shingles. Asphalt shingle manufacturers will warrant shingles installed on roof slopes as low as 2 12 when these special installation procedures are followed. This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units. Manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.

Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12. That works out to about nine degrees if that works better for you. What is the minimum pitch slope of an asphalt shingle roof.

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.