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6/12 Roof Pitch

A 6/12 pitch rises 6 inches for every 12 inches of run: 26.57°, a 50.0% slope and a multiplier of 1.118.

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Roof pitch

6/12 pitch

26.6° · 50.0% · ×1.118

6/12 is 26.57°, a 50.0% slope, and the roof is 11.8% larger than its footprint.

  • Angle26.57°
  • Percent slope50.0%
  • Pitch multiplier1.1180
  • Hip and valley factor1.5000
  • Rafter per foot of run13.42 in
  • Slope class (OSHA)Steep (over 4 in 12)

Pitch is rise in inches over 12 inches of run. The multiplier turns a flat measurement into sloped length: multiply the footprint area by it to get roof area.

Planning estimate, not a quote. Disclaimer

What a 6/12 pitch looks like

At 6/12 the roof is a moderate pitch, comfortably inside the 4:12 to 9:12 range GAF says covers most US homes. The roof rises 6 inches for every 12 inches of run. That is a 26.57° angle, a 50.0% slope and a roof surface 11.8% larger than its footprint.

Roof area at 6/12

Multiply the footprint by 1.1180. For common footprints, with no overhang and 10% extra on the shingles:

Roof area and shingles at 6/12
FootprintRoof areaSquaresBundles with 10% extra
1,000 sq ft1,118 sq ft11.237
1,500 sq ft1,677 sq ft16.856
2,000 sq ft2,236 sq ft22.474
2,500 sq ft2,795 sq ft28.093
3,000 sq ft3,354 sq ft33.5111

Rafter length at 6/12

Each foot of run adds 13.42 inches of common rafter, or 1.5000 ft of hip or valley rafter per foot of common run. For some typical runs, measured to the ridge centerline:

Rise and common rafter length at 6/12
RunRiseRafter length
4 ft2 ft 0 in4 ft 5⅝ in
6 ft3 ft 0 in6 ft 8½ in
8 ft4 ft 0 in8 ft 11⅜ in
10 ft5 ft 0 in11 ft 2⅛ in
12 ft6 ft 0 in13 ft 5 in
14 ft7 ft 0 in15 ft 7⅞ in
16 ft8 ft 0 in17 ft 10⅝ in

Roofing materials at 6/12

Standard shingle installation applies. Metal Sales lists 3:12 as the minimum for its residential metal profiles, so metal roofing works at this pitch.

Can you walk a 6/12 roof?

OSHA classes any roof over 4 in 12 as steep, so 6/12 is steep for fall-protection rules. How walkable it feels depends on the surface, moisture and footwear, so plan for anchors and proper shoes. This is general information, not safety advice.

Frequently asked questions

What angle is a 6/12 roof pitch?

26.57 degrees, a 50.0% slope.

What is the multiplier for a 6/12 roof?

1.1180. Multiply the footprint area by it to get roof area. The hip/valley factor is 1.5000.

How much roof area does a 6/12 pitch add?

11.8% over the footprint. A 2,000 sq ft footprint becomes 2,236 sq ft of roof, 22.4 squares.

Is 6/12 a steep roof?

By OSHA’s definition, yes: anything over 4 in 12 is steep for fall-protection rules. GAF puts most US homes between 4:12 and 9:12.

How much does a 6/12 roof rise over a 12-foot run?

6 feet. Over a 12-foot run the roof climbs 6 feet, which is 13 ft 5 in of rafter along the slope.

Other roof pitches

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