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10/12 roof pitch in degrees

A 10-in-12 roof — 10 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.

10/12 pitch =

=39.81°

Angle

39.81°

Percent grade

83.33333%

Slope ratio

0.833333

Rafter / ft of run

1' 3-5/8"

What it means on the roof

Set a speed square to 39.81° for the plumb and seat cuts. Every foot of horizontal run adds 1' 3-5/8" of common-rafter length, so a run of 10 ft makes a rafter about ten times that. The percent grade (83.33333%) is the same slope a road sign or a laser level reads.

Nearby pitches

Pitches around 10/12

Pitch	Angle	Grade	Rafter / ft run
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"
13/12	47.29°	108.3333%	1' 5-11/16"

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