Normal Slope For Roofs

Simply put pitch is expressed as rise over run just as the grade is simply this fraction expressed as a percentage.

Normal slope for roofs.

Roof pitches exceeding the level of 9 12 or approximately 37 degrees are termed steep slope roofs. Arctan 3 12 14 0 the primary purpose of pitching a roof is to redirect water and snow. In degrees 10 2 in 12 or 1 in 6 is considered a minimum. In roofing it is expressed in inches of vertical rise over inches of horizontal run.

There are advantages and disadvantages to having a steep pitch versus a shallow or low pitch. The minimum roof pitch for shedding snow is around 30 or a 6 12 or 7 12 slope although this is not a definite as the material of your roof the direction of the snow and wind are some factors that can affect whether or not snow will slide as roofs of as little as 10 have been reported to shed snow. If this isn t practical then perform the same measurement on the underside of. With regards to metal roofing the profile refers to the shape adopted by the metal sheets when they are bent to form the panels.

Although there s isn t any standard pitch of a roof used on all kinds of sloped roofs you can determine the range of pitches by using a roof angle calculator and by considering factors like the local climate and roofing materials. The minimum roof slope for metal roofs is dependent upon the roof profile. These are utilized in residential applications. Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs.

Thus pitch is typically greater in areas of high rain or snowfall. Definitions vary on when a roof is considered pitched. The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7. The exact roof slope in degrees is given by the arctangent.

A handy roof slope estimator can help you determine if your roof slope is likely too low for shingles. Some of the most common roof pitch types are conventional slope type roofs designed with pitch ranging from 4 12 to 9 12. The majority of north american residential roofs have historically been constructed with a slope between about 4 12 and 9 12. Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled.

This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Roofs at the lower end of the range about 4 12 to 6 12 are relatively easy to walk and work on. A 4 12 pitch being 4 inches of vertical rise over one foot or 12 inches of horizontal run. Pitches above 9 12 are very highly angled and are designated steep slope roofs.

However from the wind uplift mitigation perspective a 7 12 roof slope can be considered as a two story building due to the higher overall steepness and profile of the roof. A roof slope of 7 12 is also good and can provide the additional benefit of helping minimize the effects of wind driven rain.