A 5/12 roof pitch rises 5 inches vertically for every 12 inches of horizontal run. That converts to an angle of 22.62° from horizontal, a slope of 41.7%, and a slope factor of 1.083. By U.S. building convention this falls into the conventional-slope category.
This guide covers the math, the practical implications for materials and walkability, the typical applications for a 5/12 pitch, and how it compares to its neighbours on either side of the pitch scale.
5/12 by the numbers
Pitch ratio 5/12 corresponds to exactly 22.62° from horizontal and a slope of 41.7%. The slope factor of 1.083 means actual roof surface is 8.3% larger than the building footprint underneath it.
For a 1,000 sq ft footprint, a 5/12 gable roof has roughly 1083 sq ft of actual roof surface. Order shingles, sheathing, and underlayment against the surface area, not the footprint.
| Property | Value | Notes |
|---|---|---|
| Angle from horizontal | 22.62° | Trigonometric arctan(rise/run) |
| Slope percentage | 41.7% | Rise / run × 100 |
| Slope factor (surface multiplier) | 1.083 | Roof surface is 8.3% larger than footprint |
| Rafter length per ft of run | 1.083 ft | Common rafter scales by slope factor |
| Surface area for 1,500 sf footprint | 1625 sq ft | 125 sq ft of additional roofing material |
| Slope category | conventional | U.S. residential construction convention |
| Walkability | Comfortably walkable | Affects labour cost and pace |
Where 5/12 belongs
A 5/12 pitch sits in the conventional residential range — common on ranch homes, contemporary builds, and mid-century styles.
Material options are wide open at this pitch. Asphalt shingles install with single-layer underlayment, metal panels work cleanly, and tile, slate, and wood shake all meet their minimum-pitch specs.
Material compatibility
Asphalt shingles install with standard single-layer underlayment. Architectural shingles, metal panels, wood shake (4/12 minimum), concrete and clay tile (4/12 standard), and natural slate (4/12 minimum) all install per their specs.
Walkability and labour
A 5/12 pitch is comfortably walkable in dry conditions. Roofers move freely without staging or harnesses, which keeps labour rates standard.
Wet, mossy, or icy conditions reduce walkability by at least one pitch class. Never measure or work on a roof during or immediately after rain or snow.
5/12 vs. neighbouring pitches
Compared to a 4/12 (18.43°), a 5/12 sheds water about 2.7% more efficiently and adds a noticeable degree of visual presence.
Stepping up to 6/12 (26.57°) gains you slightly more attic volume and shedding efficiency at the cost of a small increase in framing material and labour.
Need to run the numbers?Use the free roof pitch calculator on the home page to convert pitch to angle, calculate rafter length, or estimate roof area in any unit.