12 Asphalt Shingle Roof Slope

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

12 asphalt shingle roof slope.

Pitched roofs begin with with slopes greater than 3 in 12. Mansard roofs with nearly vertical faces can boast a pitch of 20 in 12. Examples of extreme slopes range from 1 4 12 almost flat to 12 12 sloping down at a perfect 45 degree angle. 18 43 asphalt shingles with special underlayment requirements 2 in 12.

Minimum required slope x in 12 minimum required slope degrees asphalt shingles. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12. 9 46 built up roof asphalt. Roof pitch area multipliers.

Asphalt shingles should never be applied to roof slopes below 2 12 2 of vertical rise for every 12 of horizontal run or 9 5. Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work. Asphalt shingles can only be installed on roof slopes of 2 12 or greater. In 12 0 25 in 12 1 19 built up roof coal tar pitch.

Asphalt shingles minimum roof slope roof pitch r905 2 2. 100 1 054 105 4ft 2. Additional underlayment protection with special application methods are required when asphalt shingles are installed on a low slope roof following the manufacturer s application instructions. This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.

For most home styles roof pitches fall in a range 4 12 a moderate slope up to 8 12 fairly steep. The 45 degree roofs seen on a frame houses are 12 in 12 but roofs can be even steeper consider the mansard roofs introduced by french second empire architects in the middle of the 1800s. Minimum required roof slope for roofing materials. Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area.

Roofing material or system. For example a 4 12 pitch roof that is 100 square feet. Use our roof pitch calculator to find the pitch of your roof. The pitch of the roof is the rise over a 12 inch run.

Asphalt shingle options a pitch of 2 12 is the minimum pitch for shingles made of asphalt so your roof just barely makes the cut off for one of the most popular roofing material options. This number corresponds to the number of inches of rise in a 12 foot run.