25 12 Roof Slope

The gentle slope of a 4 12 roof pitch falls on the cusp between moderate pitch and low pitch.

25 12 roof slope. A 4 12 roof pitch is referred to as the roof rises 4 inches in height for every 12 inches as it measured horizontally from the edge of the roof to the centerline. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Most roof s have a pitch in the 4 12 to 9 12 range. The table below shows common roof pitches and the equivalent grade degrees and radians for each.

Definitions vary on when a roof is considered pitched. The following table shows how the same common roof slopes can be expressed using rise in run ratios degrees and percentages. It s just a little math. A pitch over 9 12 is considered a steep slope roof between 2 12 and 4 12 is considered a low slope roof and less than 2 12 is considered a flat roof.

The exact roof slope in degrees is given by the arctangent. In degrees 10 2 in 12 or 1 in 6 is considered a minimum. Arctan 3 12 14 0 the primary purpose of pitching a roof is to redirect water and snow. See below after the table for directions on how to convert any roof slope from one form to another even roof slopes not shown in the table.

Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof. Also see our page quick reference. Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio. Thus pitch is typically greater in areas of high rain or snowfall.

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 is a term describing how steep or flat your roof slope is.