Pitched Roof Slope Angle

Roof pitch and corresponding angles.

Pitched roof slope angle. 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. In the roofing trade the go to term is pitch and it is expressed in terms of 12 inches so the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally. A 4 12 pitch is around 18 5 degrees but not exactly. Often you express roof pitch as the ratio between the rise and the run in the form of x 12.

A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. You can also divide the rise over run multiply by 100 and get a percentage. Thus a 4 12 pitch would be a 33 slope. Roof pitch refers to the slope which the rafter creates.

This is useful because sometime you may need to cut a bevel with your circular saw that is not calibrated using roof pitch style this setting on circular saws is calibrated in degrees. Angle the angle of a roof is the same as the roof s slope except instead of being represented as x 12 it is represented in degrees. On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length.