Roof Cost Calculator: Squares, Pitch and Material
Enter your home's footprint, roof pitch, material and number of old layers to see a low, typical and high 2026 roof replacement estimate.
Estimate at a glance2026
Enter your footprint including overhangs, then pick pitch, material and old layers. The calculator converts your footprint to roof surface area, applies 2026 installed prices per square foot, and adds tear-off, a decking allowance and a permit. It runs in your browser and saves nothing.
Calculator
This calculator does the same multiplication a roofer does before quoting: roof area times a price per unit, plus the line items every complete roof needs. Every number it uses is listed below with its source, so you can see exactly where your estimate comes from.
How the calculator works
- Footprint to roof area. Your footprint is multiplied by a pitch factor, because a sloped roof has more surface than the floor under it. A 6/12 roof has about 12% more area than its footprint; a 12/12 roof about 41% more.
- Material price. The roof area is multiplied by the 2026 installed price per square foot for the material you pick.
- Tear-off. Removing old roofing is priced per square foot of roof, higher for two layers than one.
- Decking and permit. A fixed allowance for replacing soft plywood, and a typical permit fee.
The low figure uses the bottom of every range and the high figure uses the top. The typical figure is the midpoint.
The numbers behind it
| Item | 2026 price used |
|---|---|
| 3-tab asphalt shingles, installed | $3.43 to $4.65 per sq ft |
| Architectural asphalt shingles, installed | $4.11 to $5.57 per sq ft |
| Premium architectural shingles, installed | $4.39 to $5.95 per sq ft |
| Metal panels, installed | $8 to $14 per sq ft |
| Concrete or clay tile, installed | $10 to $18 per sq ft |
| Tear-off, one layer | $0.40 to $2.00 per sq ft |
| Tear-off, two layers | $1.00 to $3.00 per sq ft |
| Decking replacement | $2.20 to $3.00 per sq ft |
| Permit | $100 to $500 |
| Roof pitch | Area multiplier |
|---|---|
| 4/12 | 1.05 |
| 6/12 | 1.12 |
| 8/12 | 1.20 |
| 10/12 | 1.30 |
| 12/12 | 1.41 |
Getting your footprint right
Measure the outside of the house, then add about a foot on every side for the overhang. For a two-story home, use the footprint of the roof, not the total living space: a 2,400-square-foot two-story house might have a roof footprint closer to 1,300 square feet plus any single-story sections. If your roofer ordered an aerial measurement report, use its number instead. It is more accurate than any tape measure.
What the calculator does not include
- Extra labor for roofs with many valleys, dormers, skylights or chimneys
- Replacing gutters, skylights or chimney work
- Structural repairs beyond a decking allowance
- Local price differences between regions and cities
If your roof has any of these, expect your quotes to sit toward the high figure or above it. The full method, with the line items to look for in every bid, is in our roof replacement cost guide, and the wider picture of repairs, insurance and red flags is in the roofing costs guide.
Using the result with real quotes
Put your typical figure next to each bid. A bid far below it usually leaves something out, most often decking or tear-off of a second layer. A bid far above it should explain why: steep pitch, access, premium materials or extra scope. Then check every line with our guide to reading a contractor quote.
Questions homeowners ask
How accurate is this roof cost calculator?
It gives a national planning range using 2026 installed prices. Your real price depends on local labor rates, roof complexity and access, so use it to check quotes rather than replace them.
What footprint should I enter for a two-story house?
Enter the area the roof covers, measured from outside wall to outside wall plus about a foot of overhang on each side, not the total living space.
Does the estimate include tear-off?
Yes. Choose one or two old layers and the calculator adds removal priced per square foot of roof area.
Is my information saved?
No. The calculator runs entirely in your browser and does not send or store what you enter.
Sources
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