How we estimate roof costs
Every dollar figure on this site is a budgeting estimate. It is not a quote, not a median of invoices, and not a count of building permits. A local contractor’s written price is the number that matters for your house.
National asphalt band
The site uses one national band for a typical asphalt-shingle replacement on an average single-family home: $5,800 to $19,800, with $9,500 as the planning average. The roof replacement cost guide describes that band as an editorial summary of published 2026 totals for asphalt replacement (about $5,800 to $20,000) and of national averages discussed in that same range, roughly $9,500 to $10,800. We do not redistribute a third-party dataset. If a narrower source is required, use a written quote.
Installed price per square foot
The calculator, the national guide, and the state tables share one rate card. Rates are installed material and labor, per square foot of roof, before the old roof is torn off. A roofing square is 100 square feet.
| Material | Installed, per sq ft of roof, before tear-off |
|---|---|
| Asphalt 3-tab shingles | $3–$5 |
| Architectural asphalt shingles | $4–$8 |
| Metal (steel panels or standing seam) | $7–$18 |
| Clay or concrete tile | $7–$25 |
| Cedar shake | $6–$15 |
| Slate | $15–$30 |
| Flat or low-slope membrane (TPO, EPDM, PVC) | $4–$12 |
The asphalt replacement band on state pages runs from the 3-tab low end ($3 per sq ft) to the architectural high end ($8 per sq ft), then adds tear-off.
Tear-off, pitch, and rounding
- Tear-off of one old layer is added at $1.25 per sq ft. The cost guide notes published tear-off prices of about $1 to $3 per sq ft, and up to about $5 on flat roofs. We use $1.25 as a single planning figure, not as a local bid.
- A medium pitch (about 5:12 to 7:12) converts one-story floor area to roof area with a factor of 1.18, which includes a small overhang allowance. A two-story home with the same floor area is modeled as about half that roof.
- Totals are rounded to the nearest $100. Per-square-foot state rates are rounded to the nearest quarter or half dollar on the page that shows them.
How a state range is produced
Each state has an editorial low and high for a typical asphalt replacement. The cost factor is that range’s midpoint divided by the national midpoint of $12,800. The state’s planning average is $9,500 times that factor, rounded to $100. The same factor scales the per-square-foot card above. It is not a regional price index from the Bureau of Labor Statistics, and “Nth most expensive” on a state page only orders these editorial bands.
City bands are editorial estimates for an average home in that metro. They sit near the state band and move when the city’s own note calls for it (tile and flat roofs, hurricane codes, high local labor). They are not medians from permit records.
State cost pages that only repeat this formula are not included in the sitemap. Eight states stay indexed because they add a statute, code, or insurance-regulator note with a source link: California, Colorado, Florida, Georgia, New York, North Carolina, Pennsylvania, and Texas. Those notes are separate from the dollar math and are cited on the page.
Public sources used for rules, not for the dollar bands
These are the outside sources already cited on the cost guides. They explain law, tax, or a price index. They are not a price list for your roof.
- Bureau of Labor Statistics producer price index PCU324122324122, asphalt shingle and coating materials. The national cost guide uses it for the direction of material prices, not for a contract price.
- IRS Publication 523 and Publication 527, for the tax treatment of a roof on a home you live in versus a rental.
- Federal Trade Commission: avoiding a home improvement scam, for hiring warnings, not for prices.
- Florida’s 25% roof rule and wind-mitigation statutes, linked from the Florida cost page.
- State licensing lookups linked from each state roofers page and from the license table on that hub.
Where a page cannot point at a source for a number, the number should not be there. Email corrections through the editorial policy.