Roof Asphalt Shingles Requirements

The slope of the roof is measured by the vertical rise of the roof to the horizontal run and is expressed as a fraction.

Roof asphalt shingles requirements.

Above 85 f it is easy to tear the shingles or mar the granular coating. There are two simple rules to follow. A 4 12 roof slope means the roof rises 4 feet for every 12 feet of horizontal roof span. Fasteners for asphalt shingles shall be galvanized stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 2 67 mm shank with a minimum 0 375 inch diameter 9 5 mm head of a length to penetrate through the roofing materials and a minimum of 0 75 inch 19 1 mm thick the nails shall penetrate through the sheathing.

The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. Asphalt shingles do require that you have a minimum pitch to your roof. If you re having asphalt shingles put on your roof you will have to have a minimum slope. Fortunately the requirements are quite accommodating.

Each flashing should overlap the one below by at least 75 mm 3 but not be visible below the shingle top lap. Asphalt shingles can only be used on roof slopes of two units vertical in 12 units horizontal 2 12 or greater. Asphalt shingles continue to be the most widely installed roof covering option in north america. Imbed each step flashing in a 75 mm 3 wide application of asphaltic plastic cement and nail in place.

They won t be appropriate for all roofs.