A range with the assumptions showing

Unit costs, then a total

The roof is split into work items: tear-off, haul-away, decking allowance, underlayment, ice-and-water shield, flashing, shingles, ventilation, and a permit allowance. Each item has a quantity and a low, typical, and high unit cost for materials and labor. Pitch, stories, and extra layers change the labor. A sample overhead rate is spread through the lines so the prices are all-in and add up to the project total.

The range widens when details are missing

Confidence is about the scope and the sample data, not about a contractor. A measured square count, a known shingle tier, and a ZIP in one of the sample metros keep the band tighter. Unknown pitch, layers, deck condition, or a ZIP with no sample index widens it. The data date on this demo is March 15, 2026.

A quote is a signal, not a verdict

Lines are matched to the scope before the totals are compared. Inside the range, above it, and below it are all reasons to ask a question. A low total can leave out disposal, underlayment, or flashing. A high total can be a higher product, harder access, or a longer warranty. The app asks for those questions in plain language. It does not label anyone, and it does not produce a fraud score.

Sample data, on purpose

Every dollar in this demo comes from lib/data/roofing-costs.ts and the ZIP index in lib/data/regions.ts. Each dataset carries provenance: source, date, geography, sample size, and type. Today the type is a modeled estimate, the sample size is empty, and the geography is a US composite plus a few illustrative metros. Replace those files with rights-cleared local costs before anyone relies on a figure. Resale value is not part of this demo. A cost-versus-value report is a different question from what the work costs.

What this demo does not do

• It does not read PDF proposals. Paste the lines or type them, then confirm the categories.
• It prices asphalt shingle roofing only. Other trades are not estimated.
• It does not look up a live license, bind insurance, or store a project on a server.
• It does not introduce contractors, and nothing you enter is sent as a lead.
• It does not tell you who to hire.

For payment and hiring habits, see the FTC home repair guidance.