Vermont Radon
Menu

Radon-resistant new construction in Vermont

The Vermont Department of Health says it costs less to build a home radon-resistant ($250 to $750) than to fix a radon problem later ($1,500 to $2,500).⁠1 Either way, the EPA says every new home should be tested for radon after occupancy, even if it has radon-resistant features.⁠2

The five radon-resistant features

The Health Department’s fact sheet “Building Radon Resistant” lists these steps:⁠1

  1. A gas-permeable layer below the slab or flooring system, often a 4-inch layer of clean gravel.⁠1
  2. Plastic sheeting on top of the gas-permeable layer, which also blocks moisture.⁠1
  3. Sealing and caulking all openings in the concrete floor.⁠1
  4. A vent pipe, usually a 3- or 4-inch PVC pipe that vents above the roof.⁠1
  5. An electrical junction box in case a radon fan needs to be added.⁠1

The EPA describes the same basic features and says the cost to the builder of including them is typically less than the cost to mitigate the home after construction.⁠3

What Vermont’s energy code says

The Residential Building Energy Standards (RBES) are Vermont’s statewide residential energy code.⁠4 In the 2024 code handbook, a radon mitigation system installed following EPA Standards of Practice and documented to the homeowner is listed among the points options builders can choose from.⁠4 If you’re building, ask your builder which radon-resistant features the house will have.

Test after you move in

The EPA says to test every new home after occupancy, even if it has radon-resistant features.⁠2 If the result is 4.0 pCi/L or higher, the Health Department and EPA recommend reducing radon.⁠5 In a radon-resistant home, the junction box is there in case a radon fan needs to be added.⁠1

Test your new home

Order the Health Department Lab’s long-term kit for $25⁠6 and leave it in place for 3 to 12 months, ideally including a heating season.⁠5

Want to see levels day to day? A digital monitor measures and records radon continuously while it has power.⁠7 Use it alongside the lab test, not instead of it: CRCPD says to check a consumer monitor’s results with an approved test.⁠8

Order the $25 long-term kit See Airthings monitors Affiliate link

If you buy through the Airthings link, Vermont Radon may earn a commission at no extra cost to you. How we make money

Enter vtradon-10OFF for 10% off at checkout. Airthings ships only within the US.

The state lab kit is not an affiliate link. To order by phone, call 802-338-4736 or 800-660-9997.⁠5

Common questions

Do new homes in Vermont have radon?

High radon levels have been found in all types of homes in every area of Vermont.⁠9 The EPA says every new home should be tested for radon after occupancy, even if it has radon-resistant features.⁠2

How much does radon-resistant construction cost?

The Health Department says it costs less to build radon-resistant ($250 to $750) than to fix a radon problem later ($1,500 to $2,500).⁠1

Does Vermont’s building code require radon-resistant construction?

In Vermont’s 2024 residential energy code (RBES), a radon mitigation system installed following EPA Standards of Practice is listed among the points options a builder can choose.⁠4

Last reviewed How we source facts

Sources

9 official sources
  1. Vermont Department of Health. Building Radon Resistant (fact sheet, June 2025). Checked 2026-10-17. ↩
  2. U.S. Environmental Protection Agency. How to Protect Your Family from Radon When Buying a Newly Built Home. Checked 2026-10-17. ↩
  3. U.S. Environmental Protection Agency. Radon-Resistant Construction Basics and Techniques. Checked 2026-10-17. ↩
  4. Vermont Department of Public Service. Vermont Residential Building Energy Standards (RBES) Handbook, Fifth Edition, effective July 1, 2024. Checked 2026-10-17. ↩
  5. Vermont Department of Health. Radon in Your Home. Checked 2026-10-17. ↩
  6. Vermont Department of Health Laboratory. Radon Test Kits (Health Department Lab webstore). Checked 2026-10-17. ↩
  7. U.S. Environmental Protection Agency. Home Buyer’s and Seller’s Guide to Radon (EPA 402/K-24/001, March 2024). Checked 2026-10-17. ↩
  8. Conference of Radiation Control Program Directors (CRCPD). Consumer Digital Radon Monitors (CRCPD guidance, reprinted in The Radon Reporter, Q4 2025, p. 39). Checked 2026-10-17. ↩
  9. Vermont Department of Health. Testing for Radon in Your Home (fact sheet, July 2025). Checked 2026-10-17. ↩

A radon reminder each fall