Minimum Roof Slope For Snow

Minimum pitch for corrugated metal roof.

Minimum roof slope for snow.

In case a slope greater than this is necessary then a double underlayment application must be used as per the requirements of the international building code. Begin by measuring 12 inches on your level and marking it with a pencil. 18 43 asphalt shingles with special underlayment requirements 2 in 12. On roof slopes between 4 12 and 6 12 rough textured roofing materials work best.

Roofing material or system. If your roof is pitched enter the length and width of the flat area covered by the roof. You can enter this value either as a ratio x 12 or as an angle whichever suits you better. Intuitively this is the number of inches of snow on your roof in the place where the cover is the thickest.

Metal roofing systems have a good track record of performance in harsh winter environments as long as they are properly designed. The minimum pitch for shingles is 1 6 which is equivalent to 4 inches rise to 24 inches run. There are some opinions that standing seam metal roof minimum slope is 12 but it increases the possibility of leaking on the few first days of snow arrival. Minimum required slope x in 12 minimum required slope degrees asphalt shingles.

In 12 0 25 in 12 1 19 built up roof coal tar pitch. In country with heavy snow and tough winter days the metal roof minimum slope is recommended to be 1 12. People have been killed by snow avalanches sliding off roofs during big snow winters. According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal.

The key factors are usually snow loading requirements adequate slope and the use of snow guards when needed. You can safely measure the roof pitch from inside your attic with a level that is either 18 or 24 inches a tape measure and a pencil. A minimum slope of 1 inch per foot is recommended in snow country. 9 46 built up roof asphalt.

Minimum required roof slope for roofing materials.