Min Roof Slope For Asphalt Shingles

For those who don t understand the roof pitch number here is a way to envision it.

Min roof slope for asphalt shingles.

9 46 built up roof asphalt. 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. The minimum requirement is 2 12.

Asphalt shingles continue to be the most widely installed roof covering option in north america. Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work. Minimum required roof slope for roofing materials. Considering the roof slope requirement is important.

According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal. 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. What precautions need to be taken to install shingles on low slopes. This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.

What slope is considered low slope for shingles. 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. This number corresponds to the number of inches of rise in a 12 foot run. Roofing material or system.

That works out to about nine degrees if that works better for you. A roof slope of 2 12 up to but not including 4 12 is considered as low in residential construction. The minimum slope for an asphalt shingle roof is 2 12. The 2 12 number is rise over run or two units of vertical for every 12 units horizontal.

Minimum slope for asphalt shingles. Shingles of all types need to have a slope to function properly. Asphalt felt paper that is tacked to the roof sheathing. Therefore the asphalt manufactures base their warranties around the minimum recommended pitch of 4 in 12.

For example if it is a very low slope water including snowmelt or. For low slopes as well as any other slope your local building department should be contacted. Why is 2 12 the minimum. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

Asphalt shingles can only be installed on roof slopes of 2 12 or greater. Asphalt composition shingles are designed to be installed on roof slopes greater than a 4 in 12 pitch. All asphalt shingle roofs with a pitch of 4 12 or more have an underlayment of 15 lb. Asphalt shingles minimum roof slope roof pitch r905 2 2.

The requirements for an asphalt shingles roof are contained in the international building code. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.