Roof Replacement Cost Calculator

A typical asphalt roof replacement runs $8,000 to $16,000 for an average U.S. home, or $350–$750 per roofing square installed. Metal runs $900–$1,600 per square and slate $1,500–$3,000. Your state's labor rates move the total more than any other single factor.

A roofing square is 100 square feet of roof surface — the unit contractors quote in. Three bundles of asphalt shingles cover one square. Your roof area is always larger than your home's floor area, because pitch and overhangs add 5–40% more surface.

Measure the length and width of the footprint your roof covers at ground level, multiply them, then multiply by the pitch multiplier. A 6/12 pitch multiplies by 1.118; a 12/12 pitch by 1.414. This calculator does that math for you once you enter the dimensions.

A 2,000 sq ft home usually has 2,200–2,600 sq ft of roof — roughly 22–26 squares — which costs about $10,000–$19,000 for architectural asphalt, or $20,000–$40,000 for metal. Pitch moves that number more than anything else.

Labor is typically 40–60% of the total bill, at roughly $150–$300 per square. It tracks local wages, which is why we price it from published BLS wage data for your specific state rather than a national average.

In most U.S. municipalities, yes — a full replacement requires a permit costing $250–$700. Your contractor normally pulls it. Get written confirmation that they will and that the cost is included, because unpermitted work can void insurance and surface at resale.

An overlay saves $1,000–$2,000 in tear-off, but it hides any rot underneath, adds weight, shortens the new roof's life, and can void the manufacturer warranty. Most codes also cap you at two layers. It is rarely worth it.

In most states, sales tax applies to materials but not to labor on a real-property improvement — though the rules vary and some states tax the whole contract. This calculator applies your tax rate to materials only, and you can adjust the rate to match your locality.

A new asphalt roof recoups around 61% of its cost at resale — the highest recoup rate of any roofing material. The bigger value is defensive: it removes a major buyer objection and prevents water damage, which costs far more than the roof.

Two to five days of on-site work for a typical 20–25 square roof, once the crew starts. The whole process usually takes 4–8 weeks including collecting quotes, permit approval, and scheduling.

Late winter and early spring, when crews have gaps in the calendar. Demand peaks in late summer and immediately after storms, when contractors have no reason to negotiate — and when storm-chasing outfits appear.

Materials cost roughly the same for every contractor in your town — they buy from the same suppliers. When two bids differ by thousands, it is almost always labor, overhead, or scope. Ask what changed, and compare the square count.