12 Asphalt Shingle Roof Slope

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.

12 asphalt shingle roof slope.

Resilient asphalt shingles lie much flatter to the substrate than slate tile and concrete which keeps water from being easily blown under them. Mansard roofs with nearly vertical faces can boast a pitch of 20 in 12. Asphalt shingles minimum roof slope roof pitch r905 2 2. 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. Some people recommend not installing asphalt shingles on slopes below 5 12 but a skilled roofer may well be able to make this work. Roofing material or system. 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. 9 46 built up roof asphalt. 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. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

For example a 4 12 pitch roof that is 100 square feet. The pitch of the roof is the rise over a 12 inch run. Roof pitch area multipliers. Pitched roofs begin with with slopes greater than 3 in 12.

Minimum required roof slope for roofing materials. Asphalt shingles can only be installed on roof slopes of 2 12 or greater. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles. There are differing opinions as to the minimum slope for a roof but the generally accepted minimum is 3 12.

Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area. In 12 0 25 in 12 1 19 built up roof coal tar pitch. 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 means for every 12 horizontal units the roof must rise a minimum of 2 vertical units.

Asphalt shingles continue to be the most widely installed roof covering option in north america. For most home styles roof pitches fall in a range 4 12 a moderate slope up to 8 12 fairly steep.