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Last reviewed October 16, 2026

How Our Radon Cost Estimates Are Built

How Radon Mitigation Costs builds its cost ranges and ZIP results: which sources we use, how the math works, what is our own estimate, and how pages are reviewed.

Where the numbers come from

EPA for radon zones, action levels and its 2010 cost table (always labeled as 2010 dollars); state radon programs for test results (Pennsylvania DEP's test data set and the Ohio Department of Health county dashboard so far); the Census Bureau ZCTA-to-county file for ZIP areas; and HomeGuide's February 2026 national survey for current installed prices, used because no agency publishes them. Every source is listed on the sources page.

How the calculator works

The calculator takes a published installed-cost range for the system that fits your foundation, multiplies it by any size, foundation-mix and pipe-route multipliers you pick, then adds extra suction points, a permit and a retest. Low ends add up to the low total and high ends to the high total, rounded to the nearest $10. The math runs in your browser and your inputs are not sent to us. See the worked example.

What is our own estimate

The multipliers and the per-point add-on are Cornelia Cove estimates and are marked est. everywhere they appear. Everything else traces to a cited source.

How the ZIP lookup works

  1. ZIP to county: each ZIP area goes to the county covering most of its land in the Census Bureau 2020 relationship file. We keep the other counties too.
  2. County to zone: the county's zone from EPA's Map of Radon Zones file.
  3. State overlay: Pennsylvania DEP basement tests by ZIP; Ohio Department of Health county figures.
  4. Static files by 3-digit ZIP prefix, loaded only after you enter a ZIP. Nothing you type is stored.
  5. The limits shown on the lookup page apply to every result.

Thresholds and updates

Pennsylvania ZIP figures are shown only where DEP data has at least 30 basement tests. State data is refreshed when the source updates. A last-reviewed date changes only with a real data or rule change.

Health content

Health statements use EPA and state radon program wording only. We make no medical claims.

Who prepares the pages

Cornelia Cove LLC prepares these pages and checks every figure against the sources listed on each page.

Corrections

Send corrections through the contact form, naming the page and the figure. Publisher: Cornelia Cove LLC, 418 Broadway, Ste N, Albany, NY 12207.