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Roof Replacement Cost Calculator

Estimate what a re-roof should cost — by size, pitch, material, tear-off, and region. You get a low-to-high price range with the material, labor, and tear-off broken out.

Inputs

Ground-floor footprint — we add for roof pitch and waste.

Result

Adjust the inputs to see your result.

How the estimate works

Roofers price by the "square" — 100 square feet of roof surface. The calculator first turns your home's footprint into actual roof area by applying a pitch multiplier (a steeper roof has more surface for the same footprint), adds 10% for waste and starter/ridge, and divides by 100 to get squares.

Each material has a national installed-cost range per square that already blends material and labor — from about $350–475 for 3-tab asphalt up to $1,500–3,000 for natural slate. Tear-off is added separately (roughly $125 per square per existing layer), and then complexity, number of stories, and your region scale the whole thing up or down. The result is an honest low-to-high range, because real roofing bids vary that much.

What drives the price

  • Material is the biggest lever — slate or standing-seam metal can cost 4–5× an asphalt roof.
  • Pitch adds both surface area and labor difficulty. A 12:12 roof can't be walked without staging.
  • Tear-off and deck repair are the wildcards — rotten sheathing hidden under old shingles is the most common budget-buster.
  • Region swings labor by 40% or more between rural South and coastal metros.

Common mistakes

  • Pricing by footprint, not roof area. A 1,700 sq ft house can have 2,200+ sq ft of roof once pitch and overhangs are counted.
  • Forgetting tear-off and disposal. Dumpster and labor to strip two layers is real money.
  • Choosing slate or tile without a structural check. They weigh 3–4× asphalt; your framing may need reinforcement.
  • Taking one bid. Roofing bids for the same job routinely vary 30–40%. Always get three.

When this calculator is the wrong tool

Use a pro inspection for: structural repairs, low-slope/flat commercial membranes (EPDM/TPO priced differently), insurance-claim scope, or historic slate restoration. This tool estimates a standard residential re-roof.

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FAQ

Questions, answered

How much does it cost to replace a roof?
For a typical 1,700–2,000 sq ft home with architectural asphalt shingles and one layer torn off, most homeowners pay roughly $9,000–$20,000 installed, with the national midpoint around $12,000–$15,000. Metal, tile, and slate cost two to five times more. Your final price depends on roof size, pitch, material, and local labor rates.
What's a 'square' in roofing?
A roofing square is 100 square feet of roof surface — the unit roofers price by. A 2,000 sq ft roof is 20 squares. This calculator converts your house size and roof pitch into squares, then prices the material and labor per square.
Does a steeper roof cost more?
Yes, two ways. A steeper pitch means more actual roof surface area for the same footprint (the calculator applies a multiplier), and steep roofs need staging and fall protection, which raises labor. Very steep roofs also attract fewer bids, pushing prices toward the high end.
Should I tear off the old roof or go over it?
Tearing off costs more now (roughly $100–$200 per square) but lets the crew inspect and repair the deck, and it resets the roof's life. Roofing over an existing layer is cheaper but most codes allow only two total layers, and you can't see rot underneath. For a long-term roof, tear off.
Is this an exact quote?
No — it's a planning estimate built from national average cost ranges. Roofing prices swing widely by region, season, and crew. Always get 2–3 written bids from licensed local roofers before budgeting.