How we estimate roof replacement cost
Every estimate combines a national price for each part of the job with a local labor adjustment for your state. Here is exactly how that works and where the numbers come from.
The formula
For each line item we multiply a quantity (driven by your roof size, pitch, stories, and material grade) by a national unit cost, then apply a quality-grade factor. A regional labor multiplier is applied to the labor portion only — materials are priced nationally. We show the itemized result as a ±15% range.
National unit costs
| Line item | National unit cost | Source |
|---|---|---|
| Tear-off | $1.10 / sq ft | ref |
| Underlayment | $0.40 / sq ft | ref |
| Roofing material | $1.95 / sq ft | ref |
| Installation labor | $2.50 / sq ft | ref |
| Flashing & vents | $0.30 / sq ft | ref |
| Disposal | $0.30 / sq ft | ref |
Regional labor multipliers
Each state's labor multiplier is its mean roofer wage relative to the national mean, from the U.S. Bureau of Labor Statistics Occupational Employment & Wage Statistics (Roofers, SOC 47-2181). Multipliers are bounded to a sane range and applied to the labor share of each line item, so materials stay nationally priced while labor tracks local wages.
Data vintage & limitations
Compiled June 2026 from public cost aggregators and government wage data — these are derived estimates, not live contractor quotes. Local prices vary with project complexity, access, and material availability; always confirm with a licensed contractor before budgeting.