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Roofing Material Calculator

Calculate shingles and roofing materials needed
Enter roof dimensions (one side). Measurements should be from eave to ridge.
Ridge to eave
Along the ridge
Rise over run (inches)
Typical: 10-15%

Enter roof dimensions to calculate materials needed.

Roofing Calculator Guide

How to Calculate Roofing Materials

1. Measure Your Roof

Measure from ridge to eave (length) and along the ridge (width). For complex roofs, break into sections.

2. Determine Roof Pitch

Pitch is rise over run (e.g., 4/12 = 4" rise per 12" run). Steeper roofs need more materials.

3. Add Waste Factor

10-15% waste is typical for cuts, mistakes, and future repairs.

4. Calculate Squares

1 roofing square = 100 sq ft. Most shingles come 3 bundles per square.

Material Coverage Rates

  • Shingles: 3 bundles = 1 square (100 sq ft)
  • Underlayment: 1 roll ≈ 400 sq ft
  • Ridge Cap: 1 bundle ≈ 35 linear feet
  • Drip Edge: 10 ft pieces
  • Nails: ~2 lbs per square
Pro Tips
  • Order Extra
    Buy 10-15% extra for waste, future repairs, and color matching.
  • Ventilation
    Don't forget ridge vents and soffit vents for proper attic ventilation.
  • Weather
    Install in dry weather (50-85°F) for best adhesion.
Common Roof Pitches
  • 2/12 - 4/12: Low slope
  • 4/12 - 6/12: Standard pitch
  • 6/12 - 9/12: Steep pitch
  • 12/12+: Very steep

Frequently Asked Questions

Q: How many bundles of shingles do I need?

A: Calculate your roof area in square feet, divide by 100 to get "squares," then multiply by 3 (most shingles come 3 bundles per square). Add 10-15% for waste.

Q: What is a roofing square?

A: A roofing square equals 100 square feet of roof area. It's the standard unit of measurement in the roofing industry.

Q: How does roof pitch affect material needs?

A: Steeper roofs have more surface area than their flat footprint. A 12/12 pitch roof has about 41% more area than a flat roof of the same footprint.

Q: Do I need underlayment?

A: Yes! Underlayment (felt paper or synthetic) is essential for waterproofing and is required by most building codes. It goes under the shingles.

Q: What about valleys and hips?

A: Complex roofs with valleys, hips, and dormers require more materials due to additional cuts and waste. Consider increasing your waste factor to 15-20%.

Q: How long do asphalt shingles last?

A: Standard 3-tab shingles last 15-20 years. Architectural shingles last 25-30 years. Premium shingles can last 40-50 years with proper installation and maintenance.

Disclaimer

Important Notice:

  • This calculator provides estimates only. Actual material needs may vary based on roof complexity, waste, and installation method.
  • Always consult with a licensed roofing contractor for accurate measurements and professional installation.
  • Costs shown are approximate and vary by location, brand, quality, and market conditions.
  • Safety first: Roofing work is dangerous. Use proper safety equipment and consider hiring professionals.
  • This tool does not account for complex roof features like dormers, valleys, chimneys, or skylights. Add extra materials for these features.
  • Check local building codes and obtain necessary permits before starting any roofing project.
  • We are not responsible for any errors, omissions, or damages resulting from the use of this calculator.

Always verify calculations and consult professionals before purchasing materials or starting work.

Roofing Calculator

Calculate all the materials you need for your roofing project. Get accurate estimates for shingles, underlayment, and accessories!

Roofing Basics
1 Square 100 square feet of roof area
Shingle Bundle 3 bundles = 1 square (typically)
Roof Pitch Rise over run (e.g., 4/12)
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Roofing Resources:

Did You Know?

The average roof replacement costs $5,000-$10,000 for materials and labor. Proper material estimation can save you hundreds of dollars!