Propper Roof Pitch For Snow

This has more to do with weather conditions than pitch.

Propper roof pitch for snow.

Snow can certainly slide off of a 4 12 roof. Some metal building manufacturers will not warranty a roof with a 1 4 inch slope. The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions. The safest way to determine the pitch of an existing roof is to measure from inside your attic using a level tape measure and pencil.

Roof pitch is a measurement of a roof s slope expressed as a ratio. If you are building a new roof however consider the climate to determine the correct pitch and proper materials. This will extend the life of your roof. High pitch roof pros.

A 1 4 inch slope may work in alabama but one can expect leaks in minnesota or. Care must be given so that debris does not collect and thus cause damage. Slopes greater than 6 12 will tend to shed snow regardless of the texture of the material on them so roof slopes should be configured to avoid shedding anywhere people might be walking or exiting. The purpose of pitching a roof is to enable water and snow to run off so the greater the amount of rain and or snow an area receives the greater the amount of pitch needed for the roof.

When the snow piled up on the roof melting occurred and ice dams resulted in water ponding 3 inches deep. Importance of a roof pitch. The chief reason for having a roof pitch is to redirect water and snow away from the roof and avoid any percolation that might result from stagnation of water on the roof. The higher the roof pitch the more often the snow slides off.

Therefore attic space can be at a premium with a low pitch roof. So in general the shallower pitch can be more dangerous with bigger slides. Flat roofs are common with industrial buildings boasting wide roof spans and are also popular in dry climates for houses where there is no need for the roof to help disperse rain and snow. Even in these arid regions so called flat roofs are still installed with a slight pitch to keep water from pooling on top of the structure.

Although there is no single standard roof pitch used on all sloped roofs factors such as roofing materials and local climate help to determine the appropriate range of pitches for a given building. In snow country i want a 9 12 minimum and a 12 12 is preferable. However the larger factor is that when the sun comes out radiant heat passes through the snow is reflected outward melts the snow from underneath and causes it to slide. Since the pitch of the roof is lower it can act as a catch all for tree limbs and other debris.

We use full ice and water shield protection in low pitch roofs 5 12 and under. The ratio between width and height is much smaller with a low pitch roof. Metal roofs leak under these circumstances.