What is roof pitch in degrees?
Short answer. Roof pitch in degrees is the angle the roof makes with horizontal: 1/12 is about 4.8 degrees, 4/12 about 18.4, 6/12 about 26.6, 8/12 about 33.7, 10/12 about 39.8, and 12/12 is exactly 45 degrees. Any pitch converts with the formula angle = arctan(rise / 12).
Pitch to degrees chart
- 1/12 = 4.8 degrees
- 2/12 = 9.5 degrees
- 3/12 = 14.0 degrees
- 4/12 = 18.4 degrees
- 5/12 = 22.6 degrees
- 6/12 = 26.6 degrees
- 7/12 = 30.3 degrees
- 8/12 = 33.7 degrees
- 9/12 = 36.9 degrees
- 10/12 = 39.8 degrees
- 11/12 = 42.5 degrees
- 12/12 = 45.0 degrees
- 14/12 = 49.4 degrees
- 16/12 = 53.1 degrees
- 18/12 = 56.3 degrees
- 21/12 = 60.3 degrees
- 24/12 = 63.4 degrees
Degrees back to pitch
Multiply the tangent of the angle by 12 to get the rise. A phone app that reads 25 degrees means a rise of about 5.6, so roughly 5.5/12; 35 degrees works out to about 8.4/12. Apps are handy for a rough number, but a level and tape in the attic is more accurate.
What each range means
- Under 2/12 (under about 9.5 degrees): too flat for shingles; needs a membrane or standing seam metal.
- 2/12 to 4/12: shingles allowed with double underlayment or the manufacturer's low-slope method.
- 4/12 to about 8/12: the conventional, walkable range on most homes.
- About 8/12 to 12/12: steep; staging and harnesses, and usually a steep labor charge.
- Above about 21/12 (60 degrees): mansard territory, where shingle makers call for their steep-slope method with extra nails and hand sealing.
Pitch also scales the roof area; see how roofers measure a roof. For roof shapes and parts, see roof anatomy explained.