Roof Pitch Ratio Definition

However most often a ratio of pitch also fraction is slang used for the more useful slope of rise over run of just one side half the span of a dual pitched roof.

Roof pitch ratio definition.

A roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch. Sometimes pitch is also expressed in fraction form using a fraction. 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. This is the slope of geometry stairways and other construction disciplines or the trigonometric arctangent function of its decimal.

Notes to the table above. Some sources consider low slope to include 3 12 pitch roofs. Often you express roof pitch as the ratio between the rise and the run in the form of x 12. Low slope roofs are from 0 to 3 12 in pitch.

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 pitch of a roof is its vertical rise over its horizontal span. Roof pitch is used to describe the slope or angle of the roof. The slope ratio represents a certain amount of vertical rise for every 12 inches of horizontal run.

If the rise is 6 inches for every 12 inches of run then the roof slope is 6 in 12 the slope can be expressed numerically as a ratio. Roof pitch refers to the slope which the rafter creates. If asphalt shingles are to be installed on a low slope roof special steps are required to avoid short roof life and roof leaks.