Low Slope Roof Asphalt Shingles

Shingles that are not self sealing must be hand sealed with asphalt roofing cement.

Low slope roof asphalt shingles.

The usual slope for asphalt shingles is a 4 or greater rise for every horizontal foot of run. This low slope application requires a double layer of 15 felt underlayment cemented together for a distance extending from the eaves up to a point 24 inches inside the interior wall line of the building. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. A 3 per foot slope is considered low but may be acceptable if a double layer of felt is used.

What is the minimum slope for an asphalt shingle roof. The acceptable underlayment installation options for low slopes are described in the canadian standards association asphalt shingle application standard csa a123 51 as follows. Some building codes allow as low as a 2 slope with asphalt shingles if additional steps are taken. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.

Cover the entire low sloped roof area with a self adhered modified bituminous membrane that will act as an ice and water. The arma s residential manual for asphalt roofing recommends that asphalt shingles on low slope roofs be applied over a nonperforated single layer of adhesive backed bituminous membrane installed to the manufacturer s specifications or over a double layer of asphalt impregnated felt paper.