Pitch Roof Slope Angle

Divide the first part of the ratio by 12 to work out the pitch.

Pitch roof slope angle.

Find the inverse tangent of the pitch to find the angle in degrees. A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. A 4 12 pitch is around 18 5 degrees but not exactly. Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof.

Some sources consider low slope to include 3 12 pitch roofs. To do this simply convert the rise and run as a fraction to a decimal form eg. First convert the pitch to a slope. To convert between american roofing ratios and pitch degrees follow these steps.

You can assess this in two ways either as the roof pitch angles which the rafters make with the horizontal or the proportion between the run and the rise of the roof. Roof pitch refers to the slope which the rafter creates. 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. You can also divide the rise over run multiply by 100 and get a percentage.

If asphalt shingles are to be installed on a low slope roof special steps are required to avoid short roof life and roof leaks. The combination of two numbers are used to display or show the roof pitch. Low slope roofs are from 0 to 3 12 in pitch. Roof pitch is a term describing how steep or flat your roof slope is.

Rise run rise run slope. Thus a 4 12 pitch would be a 33 slope. Roof pitch angle and slope factor charts. 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.

See low slope roofing. A 12 12 pitch roof has a pitch angle of 45. Often you express roof pitch as the ratio between the rise and the run in the form of x 12. To find the angle of a roof in degrees convert the pitch to a slope then convert to degrees by finding the arc tangent of the slope.