Minimum Roof Slope For Shingles

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.

Minimum roof slope for shingles.

That works out to about nine degrees if that works better for you. 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 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. Minimum pitch for corrugated metal roof.

Pitch is measured in inches of vertical rise of the roof over one foot 12 inches of horizontal run. The minimum pitch for shingles is 1 6 which is equivalent to 4 inches rise to 24 inches run. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. Installation on roof slopes below a 2 in 12 pitch is not recommended at all.

The minimum requirement is 2 12. Determine the minimum slope of the roof based on the roofing material. Minimum required slope x in 12 minimum required slope degrees asphalt shingles. So a 4 12 pitch roof rises 4 inches for every 12 inches of horizontal run.

18 43 asphalt shingles with special underlayment requirements 2 in 12. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. Asphalt shingles continue to be the most widely installed roof covering option in north america. A shingle roof like this north dallas garage in the photo above may have a failure no matter how good a job the installer did.

Now lets get into the minimum roof slope requirements based on the. Considering the roof slope requirement is important. Minimum required roof slope for roofing materials. In 12 0 25 in 12 1 19 built up roof coal tar pitch.

Minimum roof slopes required by roofing material requirements for roof coverings section r905. According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal. 9 46 built up roof asphalt. Manufacturers of asphalt shingles recommend a pitch of 4 12 or more but the absolute minimum pitch is 2 12.

Why is 2 12 the minimum. What is the minimum slope for an asphalt shingle roof. The 2 12 number is rise over run or two units of vertical for every 12 units horizontal. Minimum roof slope roof pitch r905 2 2 asphalt shingles can only be installed on roof slopes of.

Roofing material or system. This number corresponds to the number of inches of rise in a 12 foot run.