Roof Replacement Cost: How to Budget a New Roof

A new roof is one of the bigger home projects most owners will face, and quotes can feel impossible to compare. The trick is to break the job into the same units roofers use: squares.

Roofing is priced by the square

One roofing square equals 100 square feet of roof surface. Crews estimate material and labor per square, so knowing your square count is the foundation of any budget. Use the Roofing Shingle Calculator to convert your roof’s footprint and pitch into squares and bundle counts.

Two roofs with the same floor area can need very different amounts of material because of pitch — a steeper roof has more surface and is slower and riskier to work on, which raises labor.

What goes into the total

• Tear-off and disposal — removing old layers and hauling them to the dump.
• Decking repairs — soft or rotted sheathing found after tear-off (often a per-sheet add-on).
• Underlayment, flashing, and ventilation — the parts that actually keep water out.
• Shingles or panels — architectural asphalt is the common mid-range choice; metal and tile cost more.
• Labor — the largest single line on most jobs, driven heavily by pitch and access.

A simple budgeting approach

1. Estimate your square count and bundles with the calculator.
2. Get a per-square installed price range from two or three local roofers.
3. Add a contingency (10–15%) for decking repairs you can’t see from the ground.
4. Confirm warranty terms — both the manufacturer’s material warranty and the contractor’s workmanship warranty.

Repair or replace?

Isolated damage around a single penetration or a small section of missing shingles is usually a repair. Widespread granule loss, multiple leaks, or a roof near the end of its rated life generally favors full replacement — patching an old roof rarely pays off.

These figures are planning estimates. Get on-site inspections; hidden decking damage and code upgrades can change the price meaningfully.