This roof pitch chart is the complete pitch reference: every pitch with its angle and slope multiplier, the typical pitch for each roof type, and the minimum pitch each roofing material is allowed. No sign-up.
Every common roof pitch with the three numbers you actually need: the angle in degrees, the slope multiplier (multiply your flat plan area by it to get the true roof area), and how much extra surface the pitch adds. Work yours out exactly with the roof pitch calculator.
| Pitch | Angle | Multiplier | Extra area vs flat | Typical use |
|---|---|---|---|---|
| 1/12 | 4.8° | 1.003 | +0% | Nearly flat — membranes & standing-seam metal only |
| 2/12 | 9.5° | 1.014 | +1% | Low slope — shingles only with double underlayment |
| 3/12 | 14.0° | 1.031 | +3% | Low — metal & shakes; porches and sheds |
| 4/12 | 18.4° | 1.054 | +5% | Most common house pitch — suits nearly every material |
| 5/12 | 22.6° | 1.083 | +8% | Very common — houses and garages |
| 6/12 | 26.6° | 1.118 | +12% | Common in snow country — sheds snow well |
| 7/12 | 30.3° | 1.158 | +16% | Steep — careful walking |
| 8/12 | 33.7° | 1.202 | +20% | Steep — snow country, A-frames begin |
| 9/12 | 36.9° | 1.250 | +25% | Very steep — chalets and A-frames |
| 10/12 | 39.8° | 1.302 | +30% | Very steep |
| 11/12 | 42.5° | 1.357 | +36% | Near 45° |
| 12/12 | 45.0° | 1.414 | +41% | 45° — classic steep pitch / A-frame |
Walkability rule of thumb: roofers walk up to about 6/12 comfortably, treat 7/12–8/12 as careful roofs, and use roof jacks or fall protection above that. There is no official cutoff — wet or frosty surfaces change everything.
| Roof type | Typical pitch | Snow & rain | Wind | Notes |
|---|---|---|---|---|
| Gable | 4/12 – 12/12 | Sheds well | Gable ends exposed — brace in high-wind areas | The most common roof; simplest and cheapest to frame |
| Hip | 4/12 – 8/12 | Sheds on all four sides | Best of the pitched roofs | More framing and flashing than a gable |
| Gambrel (barn) | Lower ≈ 21/12, upper 4/12 – 7/12 | Upper slope holds some snow | Broad end walls exposed | Two slopes per side — maximizes attic and storage space |
| Mansard | Lower near-vertical, top 2/12 – 4/12 | Steep faces shield the top; top behaves like a flat roof | Steep faces catch wind | Creates a full extra storey of living space |
| Shed (single slope) | 1/12 – 6/12 | Drains to one side | High wall exposed | Simplest framing; common on additions and modern homes |
| Saltbox | Unequal gable slopes, long side often 4/12 – 9/12 | Long slope holds snow | As a gable | Historic New England style; asymmetric inside |
| Butterfly | 2/12 – 6/12, sloping inward | All water funnels to one central valley — ice-dam risk | Edges lift; valley sheltered | Modern look; can harvest rainwater; drainage is critical |
| Flat / low-slope | ¼/12 – 2/12 | Carries the full snow load; ponding risk | Edge and corner suction dominate | Membrane coverings only; drainage design is everything |
| Material | Minimum pitch | Notes |
|---|---|---|
| Asphalt shingles | 2/12 | From 2/12 to 4/12, code requires double underlayment or equivalent |
| Mineral-surfaced roll roofing | 1/12 | Utility buildings and sheds |
| Clay & concrete tile | 2½/12 | Extra underlayment below 4/12; 4/12+ is the comfortable range |
| Slate | 4/12 | Heavy — check the structure can carry it |
| Wood shingles & shakes | 3/12 | Many manufacturers prefer steeper |
| Exposed-fastener metal panels | ≈ 3/12 | Some allow lower with sealed laps — check the maker |
| Standing-seam metal | ¼/12 – 3/12 | Mechanically seamed panels go lowest; snap-lock needs more |
| Membranes (TPO, EPDM, PVC, modified bitumen) | ¼/12 | Made for near-flat roofs that still drain |
Minimums are the common figures in the International Residential Code (IRC) and typical manufacturer instructions. Your local code and your product's installation guide have the final say — a covering installed below its minimum pitch can void its warranty.
4/12, 5/12 and 6/12 are the most common pitches on US houses. They shed rain and snow well, can be covered with almost any roofing material, are safe to walk during installation up to about 6/12, and keep the roof area (and cost) close to the house footprint — a 6/12 roof has only about 12% more surface than the flat plan area.
2/12 is the code minimum for asphalt shingles, and between 2/12 and 4/12 the code requires a double layer of underlayment or an equivalent membrane because water moves slowly and can back up under the laps. Below 2/12, shingles cannot be used at all — the roof needs a membrane or standing-seam metal instead. Our minimum-pitch table on this page lists the other common materials.
Steeper sheds snow better: 6/12 and above lets most snow slide off instead of building up, and metal roofing sheds at lower pitches than shingles because it is slippery. Very steep roofs (9/12+) are traditional in heavy-snow regions. Whatever the pitch, the structure still has to be built for your local snow load — pitch reduces accumulation, it does not remove the load.
The simplest way needs a 12 in level and a tape: on the roof or in the attic against a rafter, hold the level horizontal, and at 12 in from where it touches the slope, measure straight down to the slope. That drop in inches is the first number of your pitch — a 6 in drop over 12 in is a 6/12 pitch. Or type any rise and run into our roof pitch calculator and get the pitch, angle and multiplier instantly.
These figures are planning estimates only — not a guarantee and not professional advice. Mistakes are possible, including through an error in this calculator. Always check the quantities, sizes, spacings and depths with your supplier, a licensed builder, and your local building code before you buy materials or start work. The owner of this site accepts no responsibility or liability for any loss, cost, damage, injury, wasted material or failed inspection that results from using these estimates. Prices are examples to start from, not live prices or quotes.