12 Asphalt Shingle Roof Slope

Asphalt shingles can only be installed on roof slopes of 2 12 or greater.

12 asphalt shingle roof slope.

Pitched roofs begin with with slopes greater than 3 in 12. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. In 12 0 25 in 12 1 19 built up roof coal tar pitch. 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.

Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area. The pitch of the roof is the rise over a 12 inch run. 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. 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. 100 1 054 105 4ft 2. Roofing material or system. Roof pitch area multipliers.

For example a 4 12 pitch roof that is 100 square feet. Resilient asphalt shingles lie much flatter to the substrate than slate tile and concrete which keeps water from being easily blown under them. Minimum required roof slope for roofing materials. Examples of extreme slopes range from 1 4 12 almost flat to 12 12 sloping down at a perfect 45 degree angle.

This number corresponds to the number of inches of rise in a 12 foot run. Minimum required slope x in 12 minimum required slope degrees asphalt shingles. Mansard roofs with nearly vertical faces can boast a pitch of 20 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.

High and low pitch examples two examples at each end of the spectrum. Asphalt shingles continue to be the most widely installed roof covering option in north america. Asphalt shingles minimum roof slope roof pitch r905 2 2. This means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.

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.