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Free Roofing Calculator - Instantly Estimate Roof Area & Squares
Instantly estimate the total roof area and number of squares needed for your project. Includes expert tips, formulas, and answers to common questions.
Roofing Calculator
Enter your roof dimensions and slope factor to calculate area and squares.
How to Use the Roofing Calculator
Step-by-step guide to accurately calculate roof area and squares for any project.
- Measure Roof: Measure the length and width of your roof in feet.
- Determine Slope Factor: Use a slope factor (e.g., 1.12 for 4/12 pitch). See chart below.
- Enter Values: Input the length, width, and slope factor into the calculator.
- Calculate: Click Calculate to see the total roof area and squares.
Formula: (Length × Width × Slope Factor) = Area (sq ft); Area ÷ 100 = Squares
Quick Roofing Answers
Voice search and featured snippet optimized answers
How do I calculate roof area?
Multiply length × width × slope factor (all in feet).
What is a roofing square?
A square is 100 sq ft of roofing material.
How do I find the slope factor?
Slope factor: 1 = flat, 1.12 = 4/12, 1.20 = 6/12, 1.30 = 9/12.
How much extra material should I order?
Order 10% extra for waste and cuts.
Roofing Tips
- Order 10% extra shingles for waste and starter rows.
- Double-check your measurements for accuracy.
- Steeper roofs require more material due to increased area.
- Consult a pro for complex roof shapes.
Frequently Asked Questions
How do I measure a complex roof?
Break the roof into rectangles, calculate each area, then add together.
What is the best shingle type?
Architectural shingles are durable and popular for most homes.
How do I convert pitch to slope factor?
Use a slope factor chart or online calculator for your pitch.