Roofing Material Calculator
Input your house footprint and roof pitch to accurately estimate the total roofing squares and standard shingle bundles needed to complete the job.
Roofing Material Estimator
The horizontal footprint of the house (e.g. 2000 for a 40x50 house). We will calculate the true sloped roof surface area for you.
Standard is 10% for hip roofs, 15% for complex roofs with valleys.
Enter House Area
How to Calculate Roofing Material
Estimating roofing materials correctly is absolutely vital. Ordering too few shingles halts construction and wastes expensive labor hours, while ordering too many is thousands of dollars left sitting on your lawn.
What is a Roofing Square?
In the US construction industry, roof materials are not sold by the individual square foot. Instead, they are measured in Squares. One roofing square equals exactly 100 square feet of roof area.
Asphalt shingles, the most common type of roofing, are typically packaged such that three bundles equal one square. Therefore, a 2000 square foot roof requires 20 squares, meaning you must purchase 60 bundles of shingles (plus waste).
Why Roof Pitch Matters
If your house floor plan takes up 1,500 sq ft on the ground, your roof area will be significantly larger than 1,500 sq ft because it is angled upwards. The steeper the angle (pitch), the more vertical surface area is created over the same horizontal distance.
To calculate true surface area, you multiply the flat base area by a specific pitch multiplier. For a standard 6:12 roof (which rises 6 inches for every 12 inches of horizontal run), the multiplier is ~1.118. A 1,500 sq ft footprint with a 6:12 roof actually requires ~1,677 sq ft of shingles.
The Waste Factor
You must always add a safety margin to account for material cut off at edges, ridges, and valleys, as well as manufacturer defects or errors during installation.
- Gable Roof (Simple): Add 10%
- Hip Roof or Valley Intersections: Add 15%
- Highly Complex Cut-ups: Add 20%