Minimum Roof Slope For 3 Tab Asphalt Roofing

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

Minimum roof slope for 3 tab asphalt roofing. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12. Learn what the minimum slope for an asphalt shingle roof is the difference between sloped and flat roofs and how to calculate the slope of any roof. Asphalt shingles can only be installed on roof slopes of 2 12 or greater. Normal roof slope for typical installation.

18 43 asphalt shingles with special underlayment requirements 2 in 12. Asphalt shingles minimum roof slope roof pitch r905 2 2. A great many residential roofs fall into this category. 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 required roof slope for roofing materials. Traditional 3 tab shingles made with asphalt composite are the most popular type of shingle and are the most flexible in terms of adapting to many roof pitches. This number corresponds to the number of inches of rise in a 12 foot run. We do install shingles on these in between.

This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units. For those who don t understand the roof pitch number here is a way to envision it. 9 46 built up roof asphalt. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.

Roofing material or system. For example if it is a very low slope water including snowmelt or. Considering the roof slope requirement is important. If 4 12 and above is normal and 2 12 is minimum what about properties with roofs in between the two such as a 3 12 pitched roof.

Asphalt shingles continue to be the most widely installed roof covering option in north america. Therefore the asphalt manufactures base their warranties around the minimum recommended pitch of 4 in 12. The minimum slope for an asphalt shingle roof is 2 12. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

Why is 2 12 the minimum. Normal shingle installation is allowed for all roofs with a pitch of 4 12 and above. I have heard of special methods being used for 3 tab asphalt shingle and low roof pitches less than 4 pitch that includes adhering the shingles and changing the reveal so that in the roofer would be nailing through 3 layers of shingles prevents wind lift off. Asphalt composition shingles are designed to be installed on roof slopes greater than a 4 in 12 pitch.

The roofing materials most often used for these pitches include asphalt composite shingles.