Roof Slope For Snow

Building a roof with wood shakes works well in moist colder climates as they don t dry out from the snow.

Roof slope for snow.

On roof slopes between 4 12 and 6 12 rough textured roofing materials work best. For warm roofs c t 1 0 as determined from table e 3 with an unobstructed slippery surface that will allow snow to slide off the eaves the roof slope factor c s shall be determined using the dashed line in fig. If you live in a climate with cold winters and numerous snow storms a pitched roof will prevent the snow from remaining on the top of your home. The steeper the pitch the better the snow will fall to the ground.

Intuitively this is the number of inches of snow on your roof in the place where the cover is the thickest. They then have the option of putting dormers on the roof without damage to the valleys penetrations lower roofs and property below due to sliding snow and ice. This allows the snow to stay on while venting the roof system. The slope that works best seems to be 5 12.

E 2a provided that for nonventilated warm roofs their thermal resistance r value equals or exceeds 30 ft 2 h f btu 5 3 c m 2 w and for warm ventilated roofs their r value equals or exceeds 20 ft 2 h f btu 3 5 cm 2 w. In country with heavy snow and tough winter days the metal roof minimum slope is recommended to be 1 12. Roof slopes lower than 4 12 tend to perform well with metal roofs which are less prone to leakage and ice dam formation. If your roof is pitched enter the length and width of the flat area covered by the roof.