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23/12 roof pitch in degrees

A 23-in-12 roof — 23 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.

23/12 pitch =
=62.45°
Angle
62.45°
Percent grade
191.6667%
Slope ratio
1.916667
Rafter / ft of run
2' 1-15/16"
What it means on the roof
Set a speed square to 62.45° for the plumb and seat cuts. Every foot of horizontal run adds 2' 1-15/16" of common-rafter length, so a run of 10 ft makes a rafter about ten times that. The percent grade (191.6667%) is the same slope a road sign or a laser level reads.
Nearby pitches

Pitches around 23/12

PitchAngleGradeRafter / ft run
20/1259.04°166.6667%1' 11-5/16"
21/1260.26°175%2' 0-3/16"
22/1261.39°183.3333%2' 1-1/16"
23/1262.45°191.6667%2' 1-15/16"
24/1263.43°200%2' 2-13/16"
The same math, offline

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