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1/12 roof pitch in degrees

A 1-in-12 roof — 1 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.

1/12 pitch =

=4.76°

Angle

4.76°

Percent grade

8.333333%

Slope ratio

0.083333

Rafter / ft of run

1' 0-1/16"

What it means on the roof

Set a speed square to 4.76° for the plumb and seat cuts. Every foot of horizontal run adds 1' 0-1/16" of common-rafter length, so a run of 10 ft makes a rafter about ten times that. The percent grade (8.333333%) is the same slope a road sign or a laser level reads.

Nearby pitches

Pitches around 1/12

Pitch	Angle	Grade	Rafter / ft run
1/12	4.76°	8.333333%	1' 0-1/16"
2/12	9.46°	16.66667%	1' 0-3/16"
3/12	14.04°	25%	1' 0-3/8"
4/12	18.43°	33.33333%	1' 0-5/8"

All roof pitches Open the calculator

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