Roofing Calculator
Convert roof dimensions into squares, add the pitch and waste factors, and see what an asphalt shingle replacement is likely to cost.
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Estimated cost
$4,560 – $7,440
Typical figure around $6,000.
- Footprint
- 960 sq ft
- Roof area (with pitch)
- 1,073 sq ft
- Roofing squares
- 12 squares
Installed cost including tear-off. Steep or complex roofs typically land in the upper half of the range.
Planning estimate only — confirm quantities with your supplier or contractor before ordering.
How this estimate is calculated
The estimate is built from roof length (ft), roof width (ft), roof pitch and material, then priced at national average rates. It reports footprint, roof area (with pitch) and roofing squares, with quantities rounded up so you are never short of material and the standard waste allowance already included where it applies.
Installed cost including tear-off. Steep or complex roofs typically land in the upper half of the range.
The dollar range is a national average, so treat it as a starting point rather than a bid. Labor rates, permit fees and material delivery differ by region — the state table below shows how your state compares, and construction cost by state breaks the picture down further.
Prefer the longer version? Read our guide to How much does a roof replacement cost and How much does soffit replacement cost and How much does siding replacement cost.
Cost by roof pitch
Each row prices the same default job shown in the calculator above, changing only the roof pitch. Use it to see what the upgrade or the cheaper option really costs before you commit.
| Roof pitch | Low | High |
|---|---|---|
| Low (4/12) | $4,180 | $6,820 |
| Medium (6/12) | $4,560 | $7,440 |
| Steep (9/12) | $5,320 | $8,680 |
What the same job costs by state
Every row applies that state's construction cost index to the national range calculated above. The index bundles local labor rates, permit fees and material delivery, so it is a planning figure rather than a bid.
| State | Index | Low | High |
|---|---|---|---|
| Ohio | 0.92 | $4,195 | $6,845 |
| Texas | 0.93 | $4,241 | $6,919 |
| North Carolina | 0.94 | $4,286 | $6,994 |
| Georgia | 0.95 | $4,332 | $7,068 |
| Arizona | 1.01 | $4,606 | $7,514 |
| Florida | 1.02 | $4,651 | $7,589 |
| Pennsylvania | 1.03 | $4,697 | $7,663 |
| Illinois | 1.05 | $4,788 | $7,812 |
| Colorado | 1.08 | $4,925 | $8,035 |
| Washington | 1.15 | $5,244 | $8,556 |
| California | 1.32 | $6,019 | $9,821 |
| New York | 1.42 | $6,475 | $10,565 |
Index 1.00 is the national average. See construction cost by state for metro-level figures and the projects homeowners ask about most.
Where to buy materials
Links to suppliers are sponsored: if you buy through them, we may earn a commission at no extra cost to you. It never affects an estimate.
- Search The Home Depot“architectural asphalt shingles bundle”
- Search Lowe's“architectural asphalt shingles bundle”
Frequently asked questions
What is a roofing square?
A square is 100 square feet of roof surface. Shingles are sold by the square, and most residential roofs are between 20 and 40 squares.
How much extra should I allow for waste?
Add 10% for a simple gable roof, 15% for hips and valleys, and up to 20% if the roof has many dormers or penetrations.
How much does a new roof cost?
An 1,800 sq ft roof is about 20 squares once 10% waste is included. Architectural asphalt shingles installed with tear-off run $380 to $620 per square, so the job lands near $7,600 to $12,400. Metal and tile cost roughly two to three times as much.
Can I roof over the old shingles?
Only if a single layer of shingles is present and the deck is sound. Roofing over saves the tear-off cost but hides rotten decking, adds dead load, and most manufacturers will not warranty a re-roof laid over an existing layer.
Does this cost change from state to state?
Yes. Applying each state's construction cost index to the national range of $4,560 to $7,440, the same job runs from about $4,195 to $6,845 in Ohio (index 0.92) to $6,475 to $10,565 in New York (index 1.42).
What is not included in this estimate?
Installed cost including tear-off. Steep or complex roofs typically land in the upper half of the range. The figure is a national planning average for the work described above, not a contractor's quote.
