Ballpark a new roof cost by area, pitch & material
Measure the building footprint (ground area the home covers, roughly length × width) — not the angled roof surface and not your interior/attic square footage. The pitch below converts it to true roof area.
Most replacements remove one existing layer; code typically caps roofs at two layers.
Estimated total cost
$0
per sq ft
Roof Replacement Cost Estimator — guide & how to use
Ballpark only — get 2–3 written contractor quotes. This is a planning estimate, not a bid. It excludes deck/plywood repair, permits, flashing details, skylights, ridge venting, ice-and-water shield, and structural surprises. Use it to sanity-check the quotes you receive, not to negotiate a contractor below cost. All math runs privately in your browser.
What it does
This estimator turns your building footprint, roof pitch,
material, and region into a low–high installed cost range. It
converts footprint to true sloped area with a pitch factor, adds a waste allowance, prices it per
roofing square, then adds tear-off and disposal. The result is always a range, with
materials, labor, and tear-off broken out.
How to use it
Enter the roof footprint in sq ft (ground area, roughly length × width).
Pick your pitch, material, region, and complexity.
Leave tear-off on for a re-roof (turn it off only for new construction).
Read the total range, the $/sq ft of roof, and the breakdown.
Waste-adjusted area = sloped area × (1 + waste%). Steep roofs (≥ 8/12) add 3% more for handling/cutting losses (capped at 25%).
Squares = adjusted area ÷ 100. One square = 100 sq ft.
Installed rate per square (national, materials + labor): asphalt $350–$557, metal $800–$1,400, tile $700–$2,000.
Regional adjustment multiplies the rate (and tear-off, which is labor-driven). Example: asphalt $350–$557 × 1.20 in the Northeast = $420–$668 per square.
Tear-off & disposal: ~$140–$210/square for 1 layer, ~$220–$360/square for 2.
Labor vs material split: install is shown as ~60% labor / 40% materials (industry rule of thumb); tear-off is essentially all labor + disposal.
Worked example
A 1,500 sq ft footprint, 6/12 pitch (factor 1.118), asphalt,
National region, Moderate (15%) waste, tear-off 1 layer:
Install range = 19.29 × ($350–$557) ≈ $6,700 – $10,700.
Tear-off = 19.29 × ($140–$210) ≈ $2,700 – $4,000.
Total ≈ $9,400 – $14,800, or roughly $6.30/sq ft of roof (range midpoint ÷ waste-adjusted area).
Numbers round to the nearest $100 for display, and costs use the exact square footage (e.g. 19.29 squares), not the rounded display value — so your tool output may differ by a few dollars. The $/sq ft anchor divides the total by the waste-adjusted roof area that actually drove the price.
Accuracy notes & assumptions
This is a ballpark, not a quote. Real bids depend on roof access, stories, decking condition (rotten plywood adds cost), penetrations/skylights, flashing, ridge vents, drip edge, ice-and-water shield, permits, and local code.
Per-square rates are 2025–2026 national figures and drift with material prices (asphalt is petroleum-linked) and labor markets — they should be reviewed at least annually.
The 60/40 labor/material split is a rule of thumb (sources cite 50–70% labor); metal and tile skew more material-heavy than asphalt.
The pitch factor doesn't capture overhangs/eaves, which add a few percent of real area — the waste factor partially absorbs this.
Regional multipliers are coarse (5 buckets). Climate add-ons such as Northern ice-dam shield (+$500–$1,500) or coastal-South hurricane nailing/clips (+$1,000–$3,000) are not separately modeled and may add cost in your area.
Metal and tile ranges are wide because sub-types vary enormously (corrugated aluminum vs standing seam; concrete vs clay) — the range reflects that uncertainty.
Always collect 2–3 itemized written quotes; this tool's value is sanity-checking them, not replacing them.
Common mistakes this avoids
Entering the sloped surface (or attic/floor footage) instead of the footprint — that double-counts the slope.
Omitting waste — real jobs over-order 10–20% for cuts, ridge caps, and starter.
Forgetting tear-off/disposal — it's on by default here.
Applying the region multiplier to materials only — both materials and labor (and tear-off) move with region.
Frequently asked questions
How do you estimate roof replacement cost?
Start with the building footprint (flat ground area, not the angled surface). Multiply by the pitch factor to get true sloped area, add 10–20% for waste, divide by 100 for roofing squares, then multiply by an installed rate per square for your material and region. Add tear-off and disposal. This tool does it all and gives a low–high range.
What is a roofing square?
One roofing square equals 100 square feet of roof surface. Materials and labor are priced per square. A typical home is about 22–30 squares including waste — don't confuse squares with square feet.
Should I enter my house square footage as the roof area?
No. Enter the building footprint — the ground area the home covers (roughly length × width). The tool multiplies that by the pitch factor. Entering the sloped surface, or interior/attic footage, double-counts the slope.
Why is the cost shown as a range?
Real bids depend on access, stories, decking condition, flashing, skylights, permits, and local code, plus moving material and labor prices. Climate upgrades — ice-and-water shield in the North (+$500–$1,500) or hurricane clips in coastal areas (+$1,000–$3,000) — are not separately modeled and may add cost. A range is more honest for budgeting — always get 2–3 written quotes.
Does the estimate include tearing off the old roof?
Only if tear-off is checked, which it is by default since most re-roofs remove the existing layer. Tear-off and disposal add about $140–$210 per square for one layer (more for two). Turn it off for new construction or a permitted layover.
Is it really free?
Yes — 100% free, and everything runs in your browser.