Roofing Shingles Calculator
Roofing materials are sold in squares (100 sq ft each) and bundles (3 bundles = 1 square for standard architectural shingles). This calculator converts your roof footprint measurements to actual sloped surface area by applying the correct pitch multiplier, then adds your chosen waste factor for valleys, hips, and cuts. Enter roof length, eave-to-ridge width, number of sides (2 for gable, 4 for hip), and pitch to get total squares, shingle bundles, ridge cap bundles, starter strip bundles, and roofing nails. A 10% waste factor is standard for a simple gable roof with no dormers; use 15% for hip roofs and 20% for complex roofs with multiple valleys. The calculator also outputs an estimated material cost based on current architectural shingle pricing (~$35/bundle), making it easy to budget before calling suppliers.
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Top PickOwens Corning Duration Shingles — Home Depot~$34.98/bundle* Affiliate links — we may earn a commission at no cost to you.
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How to Use This Calculator
- 1Enter your measurements in the fields above. Use the units shown next to each field (ft, in, etc.).
- 2Click Calculate to get your material estimate instantly.
- 3Review the highlighted result — it shows the key quantity you need to order.
- 4Use Copy Results to save your estimate, or bookmark the URL — your inputs are encoded in the link.
Pro tip: Always add 10% to your material order to account for waste, cuts, and defects.
Frequently Asked Questions
How many bundles of shingles do I need for a 1,500 sq ft roof?
A 1,500 sq ft flat (projected) roof area requires 15 squares. At 3 bundles per square for architectural shingles, that's 45 bundles before waste. With 10% waste factor for a gable roof — or 15% for hip and valley cuts — budget 50–52 bundles. At roughly $35/bundle, that's $1,750–$1,820 in shingle materials.
What's the difference between a square and a bundle of shingles?
A roofing square is 100 square feet of roof surface. Shingles are sold in bundles, with 3 bundles making one square for standard 3-tab and most architectural shingles. Some heavyweight architectural shingles come 4 bundles per square. Check your specific product's label — it will state square footage per bundle.
How does roof pitch affect shingle quantity?
Roof pitch increases the actual surface area relative to the footprint. A 4/12 pitch roof has a slope multiplier of 1.054 (5.4% more area than flat). An 8/12 pitch has a multiplier of 1.202 (20% more area). The calculator automatically applies the correct pitch multiplier — steeper roofs need more shingles than the floor plan suggests.
How many squares of roofing do I need for a 2,000 sq ft house?
For a 2,000 sq ft house with a standard 6/12 gable roof, the actual roof surface is roughly 2,200–2,400 sq ft depending on overhang, so about 22–24 squares. At 3 bundles per square plus 10% waste, budget for 72–79 bundles. A hip roof of the same house needs 15–20% more shingles due to additional hip and valley cuts.