Methodology
Our cost data is the product, so it's worth explaining exactly how it's made and where its limits are.
Where the numbers come from
For each project we read several public cost references — established home-cost guides, manufacturer and retailer pricing, and contractor pricing pages — and synthesize them into one low–typical–high range. We report a band rather than a single source's figure on purpose: any one guide can be off, and the spread itself is useful information. We work from published facts (prices, ranges, units). We don't copy anyone's tables, prose, or images.
What we never do
We don't invent numbers. Every range traces back to the sources listed on its page, and a figure that can't be sourced doesn't get published — we'd rather show no page than a wrong one. A range is only marked verified after a human checks it against those sources; until then the page is flagged as preliminary and kept out of search.
How the estimator works
The estimator is a transparent model, not a quote engine. It starts from our published range and multiplies it by visible factors for the choices you make — home size, material tier, installation complexity. Leave everything on its default and the result equals our published range exactly; the options just narrow it. Every multiplier is shown so you can see how the number was built. It will never call itself a contractor bid, because it isn't one.
How we localize costs
City pages don't pretend we surveyed local jobs. For each metro we publish a single sourced cost factor— how that area's construction costs compare to the national average, drawn from published construction-cost indices and labor data — and apply it to our national range. The factor, the source, and the date are shown on every city page. Because materials are priced roughly nationally and labor is the main regional driver, we treat the result as an approximation and say so, rather than implying a precise local quote.
Keeping it current
Construction costs move with inflation and local labor markets, so we re-verify on a semi-annual cycle and stamp each page with the date it was last checked. Past about 200 days a page flags itself as due for review rather than quietly showing stale figures.
The honest limits
A national range can only get you in the ballpark. Your real price depends on your specific home, your local market, the materials you choose, permits, and which contractor you hire. Use our numbers to budget and to judge whether a bid is reasonable, not as a substitute for itemized written quotes.
Questions about a specific figure? Tell us — corrections are welcome.