Roof Pitch Numbers

The angle or pitch of a roof is calculated by the number of inches it rises vertically for every 12 inches it extends horizontally.

Roof pitch numbers.

A a roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Roof pitch and corresponding angles. The 7 means that the roof rises 7 for every 12 it runs.

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. This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees. Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12. 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.

Roof pitch calculator is determined by the number of inches it rises vertically for every 12 inches it extends horizontally. Commonly used roof pitches were given names such as greek. Pitches above 9 12 are very highly angled and are designated steep slope roofs. Calculate the roof pitch as the proportion of rise and run.

So the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally. Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot. Often you express roof pitch as the ratio between the rise and the run in the form of x 12. Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled.

Pitch rise run 1 5 6 25. Angle arctan pitch arctan 0 25 14. The ridge height is 1 9 to 1 7th the span an angle of 12 5 to 16. The rafters equal the span.

Roof pitch refers to the slope which the rafter creates. How to measure roof pitch. Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs. Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m.

Also referred to as roof slope or roof slant so what does the 7 12 in the example to the right mean. If a roof increases in height by four inches for every foot of horizontal run it is considered to have a 4 in 12 pitch or just a 4 pitch talk in terms of pitches and you will always be understood in the roofing universe. The most commonly used roof pitches fall in a range between 4 12 and 9 12. The rafter length is 3 4 the span about 48.

Recalculate this value into an angle. 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.