Quick answer: A roofing square is 100 sq ft of roof surface. Multiply the house footprint including overhangs by the pitch multiplier and divide by 100. A 50 × 30 ft house with 1 ft overhangs and a 6/12 roof has about 18.6 squares, or 20.5 with 10% waste.
Roofers quote by the square, shingles are packed by the square, and insurance adjusters measure in squares. Knowing your roof size helps you check quotes and plan a budget, and you can estimate it without climbing a ladder.
What Is a Roofing Square?
One square equals 100 square feet (9.29 m²) of roof surface. A 2,000 sq ft roof is 20 squares. Most asphalt shingles come three bundles per square.
Step 1: Measure the Footprint
Measure the length and width of the house at the outside walls. Then add the eave overhang on each side; overhangs of 12–24 inches are common. For a house with a garage or wings, measure each rectangle separately.
Important: use the footprint of the roof, not the living area. A two-story house with 2,000 sq ft of living space may have only a 1,000 sq ft footprint.
Step 2: Find the Pitch Multiplier
A sloped roof has more surface than its flat footprint. Multiply by the pitch factor: 1.054 for 4/12, 1.118 for 6/12, 1.202 for 8/12 and 1.414 for 12/12. Not sure of the pitch? Read our guide on how to measure roof pitch.
Step 3: Calculate Squares
Squares = (Length + 2 × Overhang) × (Width + 2 × Overhang) × Pitch multiplier ÷ 100
- House: 50 × 30 ft, 1 ft overhang: 52 × 32 = 1,664 sq ft
- 6/12 pitch: 1,664 × 1.118 = 1,860 sq ft
- Squares: 18.6
- With 10% waste: 20.46 squares, or 62 bundles of shingles
Skip the math: enter the house size, overhang and pitch to get squares, bundles, underlayment and drip edge. Open the free Roofing Calculator →
Roof Squares Chart
Squares for common footprints with 1 ft overhangs, before waste:
| House footprint | 4/12 | 6/12 | 8/12 | 12/12 |
|---|---|---|---|---|
| 40 × 25 ft (1,000 sq ft) | 12 | 12.7 | 13.6 | 16 |
| 40 × 30 ft (1,200 sq ft) | 14.2 | 15 | 16.2 | 19 |
| 50 × 30 ft (1,500 sq ft) | 17.5 | 18.6 | 20 | 23.5 |
| 60 × 30 ft (1,800 sq ft) | 20.9 | 22.2 | 23.8 | 28.1 |
| 60 × 40 ft (2,400 sq ft) | 27.4 | 29.1 | 31.3 | 36.8 |
Waste Factor
Add about 10% for simple gable roofs and 15% or more for hip roofs, valleys, dormers and skylights, where more shingles are cut. Starter strip and ridge cap are usually ordered separately.
Why Your Estimate May Differ from a Roofer’s
- Roofers measure every plane exactly, often from satellite or drone reports.
- Complex roofs with dormers and valleys have more area than a simple rectangle.
- Some quotes include waste, starter and ridge in the squares; others list them separately.
- Tear-off of multiple old layers adds cost but not squares.
Planning solar after the re-roof? See how many solar panels you need.
Frequently Asked Questions
How many squares is a 2,000 sq ft house roof?
For a single-story 2,000 sq ft footprint with modest overhangs and a 6/12 pitch, expect about 24–26 squares before waste. A two-story house of the same living area has a much smaller roof.
How many bundles of shingles are in a square?
Three bundles for most asphalt shingles. Some heavy designer shingles need four or five bundles per square.
Can I measure my roof without climbing on it?
Yes. Measure the house footprint and overhangs from the ground, estimate the pitch, and multiply by the pitch factor.
Related Guides
- Roof Pitch Explained: How to Measure It and Convert to Degrees
- How Many Fence Posts Do I Need? (With Corners and Gates)
- How Many Deck Boards Do I Need? (12×12, 12×16 and 16×20 Decks)
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