15/12 roof pitch
51.34° angle
A 15/12 roof rises 15 in for every 12 in of run: a 125% slope with a 1.601 area multiplier.
| Pitch | 15 in 12 (15:12) |
|---|---|
| Angle | 51.34° |
| Slope | 125% |
| Roof area multiplier | 1.6008 |
| Rafter length per foot of run | 19.21 in |
| Type | A very steep roof |
Roofing for a 15/12 pitch
Suitable for asphalt shingles, metal, tile and most other roofing with standard underlayment. Not walkable: roofers work from roof jacks and fall protection, which adds labor cost.
Rafter length at 15/12
| Run (half the span) | Rise | Rafter length (before overhang) |
|---|---|---|
| 10 ft | 12.5 ft | 16.01 ft |
| 12 ft | 15 ft | 19.21 ft |
| 14 ft | 17.5 ft | 22.41 ft |
| 16 ft | 20 ft | 25.61 ft |
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Other roof pitches
Questions
- What angle is a 15/12 roof pitch?
- 51.34 degrees.
- What is a 15/12 roof pitch as a percentage?
- 125%: the roof rises 15 inches for every 12 inches of run.
- What is the roof multiplier for a 15/12 pitch?
- 1.601. Multiply the roof’s flat footprint by 1.601 to get its actual surface area.
- Is a 15/12 roof walkable?
- Not walkable: roofers work from roof jacks and fall protection, which adds labor cost.