Roof cost estimator

How this works

• Sample prices until a licensed roofer supplies the table: no government or licensed source we could open publishes installed roofing prices per square by material, so the material, tear-off and permit figures are placeholders taken from a commercial pricing website. They are not a quote and not a verified source.
• Roof area = ground-floor footprint × (1 + overhang allowance) × pitch factor. The roof covers the footprint once, so a second story doesn't double it. If you only know the total living area, divide it by the number of stories. Prices are per square (100 sq ft of roof).
• Pitch factor = √(1 + (rise ÷ 12)²), rounded to 3 decimals: 1.014 at 2/12, 1.054 at 4/12, 1.118 at 6/12, 1.202 at 8/12, 1.302 at 10/12 and 1.414 at 12/12, and 1.000 for a flat or low-slope roof. This is geometry, not a sourced figure.
• The overhang allowance (10%) and the labor share of the price (50%) are assumptions with no public source. Both are labeled and editable, and a licensed roofer should set them.
• State adjustment: the U.S. Bureau of Labor Statistics median hourly wage for roofers (SOC 47-2181) in your state, May 2025, divided by the national median of $26.65. It scales only the labor share: factor = (1 − labor share) + labor share × wage ratio. These are employee wages, so they work as a relative index between states, not as a crew's price.
• Tear-off rule: International Residential Code section R908.3.1.1 says a roof recover (a new roof over the old one) “shall not be permitted” where “the existing roof has two or more applications of any type of roof covering” or “the existing roof covering is slate, clay, cement or asbestos-cement tile.” The estimator always prices a tear-off in those cases. The same section bars a recover over a water-soaked or deteriorated roof, which only an inspection can tell. The wording is quoted from the City of Coon Rapids, MN and City of East Point, GA code handouts; your local code edition and amendments may differ.
• Asphalt shingles “shall be used only on roof slopes of 2:12 or greater” (IRC R905.2.2, as quoted by Coon Rapids, MN), so the estimator won't price them on a flatter roof. Minimum slopes for other materials weren't checked for this tool.
• Heavier roofs: East Point, GA's re-roof guide requires an engineered analysis of the roof structure when the roofing material exceeds 7.5 pounds per square foot, which can matter when switching to tile or slate.
• Not included: decking replacement, ice barrier, underlayment upgrades, drip edge, ventilation and other items without a public price source. Ask each roofer to itemize them; the quote compare tool has a row for each.

Sources

• U.S. Bureau of Labor Statistics: Occupational Employment and Wage Statistics, May 2025 (Roofers, SOC 47-2181; state and national median hourly wages, series OEUN000000000000047218108 and OEUS[state]0000000000047218108, pulled from the BLS Public Data API on 2026-09-15)
• City of Coon Rapids, MN: Residential Roofing handout (quotes IRC R908.3, R908.3.1.1 and R905.2.2)
• City of East Point, GA: 2018 IRC Residential Re-Roof guide (R908.3.1.1, asphalt minimum slope, structural analysis over 7.5 lb per sq ft)

Expert review

Not yet reviewed

Last verified

September 15, 2026

Sample prices until a licensed roofer supplies the table. A planning range, not a quote or professional advice; code rules vary by local edition.