Roofing Calculator

Calculate the exact amount of shingles, underlayment, and roofing materials needed for your roof project. Get accurate measurements for roof area, roofing squares, and material costs based on your roof dimensions and pitch.

Roofing Calculator

Calculate roofing materials for your project

How to Use the Roofing Calculator

  1. Measure roof dimensions: Enter the length and width of your roof in feet.
  2. Determine roof pitch: Measure the rise over 12 inches of run (e.g., 6/12 pitch).
  3. Select roofing material: Choose from asphalt shingles, architectural shingles, metal, or clay tiles.
  4. Review calculations: Get roof area in square feet, number of squares needed, and material costs.
  5. Plan your project: Use results to order materials and estimate project timeline.

Understanding Roof Pitch

How to Measure Roof Pitch

  • • Use a level and measuring tape
  • • Measure 12 inches horizontally from the roof edge
  • • Measure vertically from that point to the roof
  • • Express as rise/run (e.g., 6/12 or 6:12)
  • • Can also be expressed in degrees or percentage

Common Roof Pitches

4/12 (Low slope):18.4° or 33%
6/12 (Standard):26.6° or 50%
8/12 (Steep):33.7° or 67%
12/12 (Very steep):45° or 100%

Roofing Material Types & Costs

Material TypeLifespanCost/SquareBest For
Asphalt Shingles15-30 years$300-$500Budget-friendly, easy installation
Architectural Shingles25-40 years$400-$700Enhanced appearance, better durability
Metal Roofing40-70 years$700-$1200Longevity, energy efficiency
Clay/Concrete Tiles50-100 years$500-$1000Durability, fire resistance

Understanding Roofing Squares

A "roofing square" is a standard unit of measurement in the roofing industry that equals 100 square feet of roof area. This measurement helps standardize material calculations and pricing across the industry.

Example Calculation:

A roof that measures 30 feet × 40 feet = 1,200 sq ft
1,200 sq ft ÷ 100 = 12 roofing squares

Why Use Squares?

  • Simplifies material ordering and cost estimation
  • Standard packaging often corresponds to square coverage
  • Makes it easier to compare contractor bids
  • Accounts for roof pitch in area calculations

Roofing Installation Tips

Safety First

  • • Always use proper safety equipment
  • • Work with a partner when possible
  • • Avoid working in wet or windy conditions
  • • Use roof brackets and safety harnesses
  • • Check local building codes and permits

Installation Best Practices

  • • Start from the bottom and work up
  • • Ensure proper shingle overlap
  • • Install underlayment for extra protection
  • • Use appropriate nails and fasteners
  • • Plan for proper ventilation

Frequently Asked Questions

How do I measure roof pitch safely?

You can measure pitch from inside the attic using a level and measuring tape, or hire a professional for exterior measurements.

How many bundles of shingles are in a square?

Typically 3 bundles equal one square (100 sq ft) for standard asphalt shingles. Architectural shingles may vary.

Should I include waste in my calculations?

Yes, add 10-15% for waste, cuts, and starter strips. Complex roofs with many angles may need up to 20% waste factor.

What other materials do I need besides shingles?

You'll also need underlayment, starter strips, ridge caps, drip edge, flashing, and roofing nails or fasteners.