How Many Squares of Shingles Do I Need?
Short answer: a roofing square is 100 square feet of roof, and it takes 3 bundles of standard shingles. A 1,800 sq ft one-story house with a 6/12 roof needs about 22 squares (67 bundles) including 10% waste.
What is a square of shingles?
Roofers measure in squares: one square covers 100 square feet of roof surface. Standard three-tab and most architectural shingles come in 3 bundles per square; some heavy designer shingles take 4 or 5. The bundle wrapper says how many square feet it covers, usually about 33.3.
Roof area is bigger than the house
A sloped roof has more surface than the floor it covers. The steeper the pitch, the bigger the difference. Multiply the footprint (including the overhang) by the pitch factor:
| Pitch | Roof factor | Adds |
|---|---|---|
| 4/12 | 1.054 | 5% |
| 6/12 | 1.118 | 12% |
| 8/12 | 1.202 | 20% |
| 10/12 | 1.302 | 30% |
| 12/12 | 1.414 | 41% |
Squares = roof area ÷ 100 × 1.10 (waste)
Bundles = squares × 3, rounded up
Not sure of your pitch? The roof pitch calculator converts rise and run to pitch and degrees.
Squares and bundles by house size
One-story house, roof footprint equal to the floor area (no overhang), simple gable roof, 10% waste:
| Footprint | 4/12 pitch | 6/12 pitch | 8/12 pitch |
|---|---|---|---|
| 1,000 sq ft | 11.6 sq · 35 bundles | 12.3 sq · 37 bundles | 13.2 sq · 40 bundles |
| 1,200 sq ft | 13.9 sq · 42 bundles | 14.8 sq · 45 bundles | 15.9 sq · 48 bundles |
| 1,500 sq ft | 17.4 sq · 53 bundles | 18.4 sq · 56 bundles | 19.8 sq · 60 bundles |
| 1,800 sq ft | 20.9 sq · 63 bundles | 22.1 sq · 67 bundles | 23.8 sq · 72 bundles |
| 2,000 sq ft | 23.2 sq · 70 bundles | 24.6 sq · 74 bundles | 26.4 sq · 80 bundles |
| 2,500 sq ft | 29.0 sq · 87 bundles | 30.7 sq · 93 bundles | 33.1 sq · 100 bundles |
Two-story house? Use the footprint of the roof, not the total living area. A 2,000 sq ft two-story home often has a roof footprint of only about 1,000 to 1,100 sq ft. Overhangs add more: a 1 ft overhang all round adds about 1 sq ft for every foot of outside wall (a 24 × 24 ft building gains 100 sq ft).
Hip roofs and roofs with valleys and dormers waste more shingles in cuts; use about 15% waste instead of 10%.
Worked example: a 24 × 24 garage
A 24 × 24 ft garage with a 1 ft overhang has a footprint of 26 × 26 = 676 sq ft. At a 6/12 pitch: 676 × 1.118 = 756 sq ft of roof, or 7.56 squares. With 10% waste that is 8.3 squares, so 25 bundles.
What else to order
- Underlayment: synthetic rolls usually cover about 10 squares each.
- Starter strip for the eaves and rakes, and ridge cap shingles for ridges and hips, both sold by linear feet.
- Drip edge for the perimeter, ice and water shield at the eaves and valleys in cold climates, and nails (about 4 to 6 per shingle).
Pricing the whole job? The roof replacement cost calculator estimates labor and materials by material type, and the metal roof calculator covers panels instead of shingles.
Try the roofing calculator
Enter your own numbers below, or open the full roofing calculator with the formula and more examples.
Frequently asked questions
How many bundles of shingles are in a square?
Three bundles for most standard three-tab and architectural shingles. Some heavy designer shingles need 4 or 5 bundles per square.
How many squares of shingles for a 1,800 sq ft house?
About 22 squares (67 bundles) for a one-story house with a 6/12 roof, including 10% waste. A two-story 1,800 sq ft house has a much smaller roof.
How many squares of shingles for 2,000 square feet?
For a 2,000 sq ft roof footprint at a 6/12 pitch, about 24.6 squares or 74 bundles with 10% waste.
How many squares of shingles for a 24x24 garage?
About 8.3 squares (25 bundles) with a 6/12 pitch, a 1 ft overhang and 10% waste.