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9/12 roof pitch in degrees

A 9-in-12 roof — 9 inches of rise for every 12 inches of run — as an angle, a percent grade, a slope ratio, and the rafter length it adds per foot of run.

9/12 pitch =

=36.87°

Angle

36.87°

Percent grade

75%

Slope ratio

0.75

Rafter / ft of run

1' 3"

What it means on the roof

Set a speed square to 36.87° for the plumb and seat cuts. Every foot of horizontal run adds 1' 3" of common-rafter length, so a run of 10 ft makes a rafter about ten times that. The percent grade (75%) is the same slope a road sign or a laser level reads.

Nearby pitches

Pitches around 9/12

Pitch	Angle	Grade	Rafter / ft run
6/12	26.57°	50%	1' 1-7/16"
7/12	30.26°	58.33333%	1' 1-7/8"
8/12	33.69°	66.66667%	1' 2-7/16"
9/12	36.87°	75%	1' 3"
10/12	39.81°	83.33333%	1' 3-5/8"
11/12	42.51°	91.66667%	1' 4-1/4"
12/12	45.00°	100%	1' 5"

All roof pitches Open the calculator

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