Low Slope Roof Asphalt Shingles

A 3 per foot slope is considered low but may be acceptable if a double layer of felt is used.

Low slope roof asphalt shingles.

They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. Some building codes allow as low as a 2 slope with asphalt shingles if additional steps are taken. 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. When combined with the proper underlayment materials and application they are an excellent solution for a low slope roof with a pitch between 2 12 to 4 12.

The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. The usual slope for asphalt shingles is a 4 or greater rise for every horizontal foot of run. 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. Asphalt shingles continue to be the most widely installed roof covering option in north america.

Cover the entire low sloped roof area with a self adhered modified bituminous membrane that will act as an ice and water. Shingles that are not self sealing must be hand sealed with asphalt roofing cement.