Low Slope Roof Shingles

Some will argue that shingles shouldn t be used for low pitch roofs at all.

Low slope roof shingles.

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. 3 tab shingles versus laminated shingles for low slope roof. Cover the entire low sloped roof area with a self adhered modified bituminous membrane that will act as an ice and water. The usual slope for asphalt shingles is a 4 or greater rise for every horizontal foot of run.

However those naysayers would be wrong. Most manufacturer and industry recommendations require or at the very least recommend special underlayment or other considerations on roofs between 2 12 and 4 12. As well a slope of 4 12 is most commonly considered the lowest slope for standard shingle installations. Shingles that are not self sealing must be hand sealed with asphalt roofing cement.

If you have a low slope roof but would love to have a shingled look rather than other solutions like rolled sheet roofing you are in luck. 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. They typically had different underlayment recommendations for low slope roofs 2 12 to 4 12 pitches but that was about it.

And by the way the manufacturers instructions i reviewed for the shingles i was interested in buying described installations down to a 2 12 pitch.