Roof pitch

Display of roof pitches 1:12 through 18:12
A roof made of thatch, one of the oldest roofing materials, needs a steep pitch to drain properly
Some types of stone roof have a very restrictive roof pitch, which can lead to leaking
Working on roofs with pitches too steep for safety requires a staging of scaffolding boards secured with roof brackets
A pitch gauge measuring the slope of an asphalt shingle roof

Roof pitch is the steepness of a roof expressed as a ratio of inch(es) rise per horizontal foot (or their metric equivalent), or as the angle in degrees its surface deviates from the horizontal. A flat roof has a pitch of zero in either instance; all other roofs are pitched.

A roof that rises 3 inches per foot, for example, would be described as having a pitch of 3 (or “3 in 12”).