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4:12 Roof Pitch

4/12 is the minimum pitch for standard asphalt shingles — a low-slope roof that's walkable, energy-efficient, and affordable to build.

🏠 Standard Pitch

Pitch Ratio

4:12

Angle

18.4°

Slope

33.3%

Rise per 12" Run

4 inches

Run: 12.0Rise: 4.018.4°Rafter

🏠 Common Uses for 4:12 Pitch

  • Modern and contemporary home designs
  • Ranch-style single-story homes
  • Porch and addition roofs
  • Mid-century modern architecture
  • Low-profile suburban homes

🌦️ Best Climate Fit

  • Moderate climates with light-to-moderate rainfall
  • Not ideal for heavy snow regions (prefer 6/12+)
  • Hot/dry climates (desert, Mediterranean)
  • Minimum pitch for wind-driven rain resistance

✅ Advantages

  • Minimum pitch where asphalt shingles perform well
  • Lower material cost (less surface area than steeper pitches)
  • Easier and safer to walk on for maintenance
  • Less attic space wasted to structure
  • Lower wind load than steeper roofs

⚠️ Drawbacks

  • ×Marginal for heavy snow loads
  • ×Shorter shingle lifespan vs steeper pitches (more UV exposure)
  • ×Limited attic headroom if space is needed
  • ×Water can pool at seams if installation is poor

🧱 Recommended Materials for 4:12

Asphalt Shingles (minimum)Architectural ShinglesStanding Seam MetalModified Bitumen

About 4:12 Pitch

A 4:12 (also written as 4/12) roof pitch means the roof rises 4 inches for every 12 inches of horizontal distance. Expressed as an angle, this is approximately 18.4 degrees, with a slope of 33.3%.

Asphalt shingles (most popular), architectural shingles, or wood shakes. Standard residential pitch range.

Compared to a flat roof of the same footprint, a 4:12 pitch roof has about 5.4% more surface area due to the slope. Factor this into your material calculations using a pitch multiplier of ×1.054.