Cost per square foot calculator

Each project type carries a broad per-sq ft range covering both labour and materials, installed. When you enter a size, the calculator multiplies the size by the low end and by the high end, then rounds to keep the result honest about being an estimate rather than a bid.

There is no attempt at false precision here. A single number would be more satisfying and less true — the range is the answer, and where your project lands inside it depends on the details below.

Contractors price by area because area is the one thing they can measure before they know anything else about your job. It rolls labour hours, material quantities, waste and overhead into a single number they can quote quickly and compare across jobs.

It's a planning tool for you too. A rate lets you sanity-check the scale of a number before you get into line items: if a quote works out to three times the typical rate, something specific is behind that, and the quote should say what.

Materials. Usually the single biggest swing. Asphalt shingle and vinyl plank sit near the bottom of their ranges; slate, hardwood and stone sit at the top, sometimes well above.

Location. Labour rates vary a lot between regions and between city and rural work — see the hourly rate calculator for how much.

Access and complexity. Height, pitch, tight lots, no driveway for a truck, stairs, corners and cut-ins all add hours without adding area.

Removal and disposal. Tearing off an old roof, floor or fence and hauling it away is real cost that a bare per-square-foot rate often excludes.

What's found underneath. Rotten decking, an unlevel subfloor or moisture damage behind siding can only be priced once it's visible. A good quote says what happens — and what it costs — if that turns up.

Permits and inspections. Often quoted separately, and sometimes left off entirely. Ask.

Economies of scale. Small jobs cost more per square foot than large ones, because mobilisation, setup and travel get spread across less area.

Two 2,000 square foot roofs can be genuinely different jobs. One is a single-storey walkable pitch with one layer to strip; the other is two storeys, steep enough to need harnesses and staging, with three layers of old shingle and four skylights to flash. Same area, very different hours.

That's why comparing two quotes means comparing scope, not just totals. Our guide to why two contractor quotes can be so different walks through the usual culprits.