12 Asphalt Shingle Roof Slope

100 1 054 105 4ft 2.

12 asphalt shingle roof slope. Asphalt shingles continue to be the most widely installed roof covering option in north america. Roof pitch area multipliers. In 12 0 25 in 12 1 19 built up roof coal tar pitch. 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.

Roofing material or system. Examples of extreme slopes range from 1 4 12 almost flat to 12 12 sloping down at a perfect 45 degree angle. 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. Pitched roofs begin with with slopes greater than 3 in 12.

Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work. Mansard roofs with nearly vertical faces can boast a pitch of 20 in 12. Minimum required roof slope for roofing materials. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

For most home styles roof pitches fall in a range 4 12 a moderate slope up to 8 12 fairly steep. 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. Asphalt shingles can only be installed on roof slopes of 2 12 or greater. Resilient asphalt shingles lie much flatter to the substrate than slate tile and concrete which keeps water from being easily blown under them.

This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units. High and low pitch examples two examples at each end of the spectrum. 18 43 asphalt shingles with special underlayment requirements 2 in 12. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12.

For example a 4 12 pitch roof that is 100 square feet. Use our roof pitch calculator to find the pitch of your roof. This number corresponds to the number of inches of rise in a 12 foot run. The pitch of the roof is the rise over a 12 inch run.

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