Roof Pitch Calculator
Roof Parameters
Vertical rise
Horizontal run
Select output format
Calculation Results
0
Roof Pitch Calculator: Your Guide to Roof Slope
Need to calculate your roof pitch? Our Roof Pitch Calculator helps you determine the slope of your roof in multiple formats, including ratio, degrees, and percentage.
Understanding Roof Pitch
Roof pitch is important for several reasons:
- Water Drainage: Proper water runoff
- Material Selection: Appropriate roofing materials
- Snow Load: Snow accumulation management
- Wind Resistance: Wind load considerations
- Aesthetic Appeal: Architectural design
How to Use the Roof Pitch Calculator
- Enter Rise: Input vertical measurement
- Enter Run: Input horizontal measurement
- Select Format: Choose output type
- Click Calculate: Get pitch measurements
Roof Pitch Calculation Formulas
Ratio (X:12):
Degrees:
Percentage:
Where:
Rise = Vertical measurement
Run = Horizontal measurement
Pitch = (Rise ÷ Run) × 12
Degrees:
Pitch = arctan(Rise ÷ Run)
Percentage:
Pitch = (Rise ÷ Run) × 100
Where:
Rise = Vertical measurement
Run = Horizontal measurement
Common Roof Pitch Standards
- Low Slope (2:12 to 4:12):
- Ratio: 2:12 to 4:12
- Degrees: 9.5° to 18.4°
- Percentage: 16.7% to 33.3%
- Use: Modern homes, commercial
- Conventional Slope (4:12 to 9:12):
- Ratio: 4:12 to 9:12
- Degrees: 18.4° to 36.9°
- Percentage: 33.3% to 75%
- Use: Residential homes
- Steep Slope (9:12 to 12:12):
- Ratio: 9:12 to 12:12
- Degrees: 36.9° to 45°
- Percentage: 75% to 100%
- Use: Traditional homes
- Very Steep Slope (12:12 and above):
- Ratio: 12:12 and above
- Degrees: 45° and above
- Percentage: 100% and above
- Use: Special designs
Real-World Examples
Example 1: Standard Residential Roof
Rise: 6 inches
Run: 12 inches
Calculation Type: Ratio
Results:
- Pitch Ratio: 6:12
- Pitch Degrees: 26.6°
- Pitch Percentage: 50%
- Classification: Conventional Slope
Example 2: Modern Low-Slope Roof
Rise: 3 inches
Run: 12 inches
Calculation Type: Degrees
Results:
- Pitch Ratio: 3:12
- Pitch Degrees: 14.0°
- Pitch Percentage: 25%
- Classification: Low Slope
Frequently Asked Questions
What is a good roof pitch?
4:12 to 9:12 is most common for residential.
How to measure roof pitch?
Measure rise and run, then use calculator.
What pitch is best for snow?
Steeper pitches (6:12 or more) better for snow.
Minimum pitch for shingles?
2:12 minimum for standard shingles.
How pitch affects cost?
Steeper pitches cost more to install.