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24/12 roof pitch in degrees

A 24-in-12 roof — 24 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.

24/12 pitch =
=63.43°
Angle
63.43°
Percent grade
200%
Slope ratio
2
Rafter / ft of run
2' 2-13/16"
What it means on the roof
Set a speed square to 63.43° for the plumb and seat cuts. Every foot of horizontal run adds 2' 2-13/16" of common-rafter length, so a run of 10 ft makes a rafter about ten times that. The percent grade (200%) is the same slope a road sign or a laser level reads.
Nearby pitches

Pitches around 24/12

PitchAngleGradeRafter / ft run
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"
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