Minimum Slope For Asphalt Shingles Roof

The minimum slope for an asphalt shingle roof is 2 12.

Minimum slope for asphalt shingles roof.

This number corresponds to the number of inches of rise in a 12 foot run. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12. What is the minimum pitch slope of an asphalt shingle roof. Shingles of all types need to have a slope to function properly.

For those who don t understand the roof pitch number here is a way to envision it. 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. Therefore the asphalt manufactures base their warranties around the minimum recommended pitch of 4 in 12. The requirements for an asphalt shingles roof are contained in the international building code.

The 2 12 number is rise over run or two units of vertical for every 12 units horizontal. All asphalt shingle roofs with a pitch of 4 12 or more have an underlayment of 15 lb. 18 43 asphalt shingles with special underlayment requirements 2 in 12. Asphalt composition shingles are designed to be installed on roof slopes greater than a 4 in 12 pitch.

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. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

Roofing material or system. Asphalt shingles continue to be the most widely installed roof covering option in north america. That works out to about nine degrees if that works better for you. According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal.

Asphalt shingles can only be installed on roof slopes of 2 12 or greater. Minimum slope 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. Why is 2 12 the minimum.

For example if it is a very low slope water including snowmelt or. 9 46 built up roof asphalt. In 12 0 25 in 12 1 19 built up roof coal tar pitch. Asphalt felt paper that is tacked to the roof sheathing.

Asphalt shingles minimum roof slope roof pitch r905 2 2. Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work.