RoofGenius

6/12 Roof Pitch

A 6/12 roof rises 6 inches for every 12 inches of horizontal run: 26.57°, a 50.0% slope, and 11.8% more surface than its footprint.

12 in run 6 in rise 26.6°
6/12 pitch at a glance
Measure6/12 value
Angle26.57°
Slope percent50.0%
Rise per foot of run6 in
Pitch multiplier (area factor)1.1180
Hip/valley factor1.5000
Common rafter length per foot of run13-7/16"
Plumb cut / seat cut26.6° / 63.4°

Where you see a 6/12 roof

Typical uses: two-story homes, colonials and a large share of new construction. A 6/12 roof is often called the most common residential pitch. At 26.6 degrees it sheds water and snow well, accepts nearly every material, and is still walkable for most roofers in dry conditions. It is a good default when a plan does not say otherwise.

Roof area at 6/12

6/12 formulas

Angle = arctan(6 ÷ 12) = 26.57° Multiplier = √(6² + 12²) ÷ 12 = 1.1180 Roof area = footprint × 1.1180 Rafter = run × 1.1180 Ridge height = run × 6 ÷ 12

Worked examples

Roof area. A 48 × 30 ft house with 1 ft overhangs has a 50 × 32 = 1,600 sq ft footprint. At 6/12: 1,600 × 1.1180 = 1,789 sq ft, or 17.9 squares before waste.
Rafter. A 28 ft span with a 1-1/2" ridge board has a 13.938 ft run. Line length = 13.938 × 1.1180 = 15' 7"; add an 18" overhang (1' 8-1/8" along the slope) for 17' 3-1/8". The ridge sits 7' 0" above the plate line. Try other spans in the rafter calculator.

6/12 rafter lengths and ridge heights

Common rafters at 6/12, measured to the center of the ridge
Building spanRunRafter (no overhang)Ridge rise
16 ft8 ft8' 11-5/16"4' 0"
20 ft10 ft11' 2-3/16"5' 0"
24 ft12 ft13' 5"6' 0"
28 ft14 ft15' 7-13/16"7' 0"
32 ft16 ft17' 10-11/16"8' 0"
36 ft18 ft20' 1-1/2"9' 0"

Roof area by footprint at 6/12

Footprint to roof area at 6/12
Footprint (incl. overhang)Roof areaSquares
1,000 sq ft1,118 sq ft11.2
1,500 sq ft1,677 sq ft16.8
2,000 sq ft2,236 sq ft22.4
2,500 sq ft2,795 sq ft28.0
3,000 sq ft3,354 sq ft33.5

Materials and walkability

  • Shingles: Yes. 4/12 and steeper takes a standard shingle installation.
  • Walkable? Generally yes, in dry conditions with proper footwear and fall protection where required.

← 5/12 pitch · 7/12 pitch → · All pitches in degrees

Frequently asked questions

How many degrees is a 6/12 roof pitch?

A 6/12 roof pitch is 26.57 degrees.

What is the multiplier for a 6/12 pitch?

The pitch multiplier for 6/12 is 1.1180. Multiply the footprint area or horizontal run by it to get the sloped area or rafter length.

Can you put shingles on a 6/12 roof?

Yes. 4/12 and steeper takes a standard shingle installation.

Is a 6/12 roof walkable?

Generally yes, in dry conditions with proper footwear and fall protection where required.

Last reviewed 2026-10-10. Results are estimates for planning; confirm quantities with your supplier and requirements with your local building code and the manufacturer's instructions.