How to Use the Roofing Calculator

  1. Select Your Roof Style

    • Choose between Gable, Hip, Flat, Mansard, or Gambrel roof styles
    • Each style may require different calculations for valleys and hips
  2. Choose Roofing Material

    • Asphalt Shingles: Most common, includes 15% waste factor
    • Metal Roofing: Includes 10% waste factor
    • Tile: Includes 20% waste factor for breakage
    • Slate: Includes 15% waste factor
  3. Select Measurement Unit

    • Choose between feet or meters based on your preference
    • All measurements will be calculated in your chosen unit
  4. Enter Roof Sections

    • Divide your roof into sections for accurate calculations
    • For each section, provide:
      • Length and width measurements
      • Roof pitch (slope)
      • Valley and hip lengths (if applicable)
    • Add multiple sections for complex roof designs
  5. Understanding Results

    • Total squares needed (1 square = 100 square feet)
    • Detailed materials list including:
      • Main roofing material
      • Underlayment rolls
      • Nails/fasteners
      • Starter strips
      • Ridge caps
      • Valley and hip materials
    • Section-by-section breakdown
    • Waste factor included in calculations

Tips for Accurate Measurements

  • Measure from the ground to ensure safety
  • Include overhangs in your measurements
  • Double-check all measurements before calculating
  • Consider adding extra material for repairs
  • Account for all roof features (chimneys, skylights, etc.)

Safety Note

Always consult with a professional roofer for final measurements and material quantities. This calculator provides estimates only and should not be used as the sole basis for purchasing materials.

Roofing Calculator