Radon in Laramie County, WY: Cheyenne Testing and Costs

Nearly all of Wyoming is high-potential radon country on EPA's map. The 1993 Map of Radon Zones rates 21 of Wyoming's 23 counties Zone 1, including Laramie County, meaning a predicted county average indoor screening level above 4 pCi/L.

The Census Bureau relationship file maps 12 ZIP areas to Laramie County; 11 sit wholly in Zone 1 counties and 1 also reaches into Zone 2 land. Wyoming does not publish household test results by ZIP, so test your home to know its level (EPA Citizen's Guide, 2016).

HomeGuide's Feb 2026 survey prices a sub-slab system at $1,200 to $2,000 installed, and Cheyenne's basement homes are the standard case for it.

Licensing and permits

No state radon license: the Wyoming Department of Health recommends hiring a radon professional certified by the National Radon Proficiency Program or the National Radon Safety Board, and points residents to those lists.

Free kits: the Wyoming Department of Health and the Wyoming State Geological Survey describe free home test kits for residents while supplies last.

Permits: the City of Cheyenne and Laramie County building offices set permit rules for the fan circuit; HomeGuide puts radon permits at $25 to $150 where required.

Ask for the post-mitigation test in writing.

Local conditions

Cheyenne sits on the High Plains, on sand, gravel and silt of the Ogallala Formation washed east from the mountains. To the west, the Laramie Range rises on Precambrian granite, the Sherman Granite, along I-80 toward Buford. Granite can carry uranium, and coarse plains gravel lets soil gas move easily.

The Wyoming State Geological Survey notes that radon comes from the natural decay of uranium in rock and soil found across the state.

Cheyenne's housing is mostly basement homes, from older neighborhoods near downtown to newer subdivisions east and north of the city along I-25 and Dell Range Boulevard. Cold winters keep houses closed and the stack effect strong.

Wind is the other local factor. Steady west winds across the plains pull air out of a house on the downwind side and draw soil gas in at the foundation, which is one reason readings can swing from week to week. A long-term test of 90 days or more, which EPA's guide describes, smooths that out better than a two-day kit.

Laramie County homeowners who already have a system should check the fan and the pipe gauge each fall before the heating season. Eastern Laramie County around Pine Bluffs and Albin is dryland farm and ranch country on the same plains sediments, with farmhouses on older basements and outbuildings converted to living space; those homes test the same way as a house in town.

What drives local prices

Basement homes on plains gravel often need a single sub-slab point, $1,200 to $2,000 based on HomeGuide's published survey.
Ranch homes on acreage outside Cheyenne may have crawlspaces; submembrane depressurization was $1,000 to $2,500 in EPA's 2010 guide (2010 dollars).
Freeze-proofing the exterior pipe and fan is a local design detail (our observation).
Permit $25 to $150 and professional retest $125 to $400 (HomeGuide).
Distance: rural parts of the county far from Cheyenne may carry a trip charge (not a published figure).

Common jobs

Sub-slab systems in Cheyenne basement homes.
Crawlspace membranes on rural ranch houses.
Systems for military families relocating near F.E. Warren Air Force Base.
Pre-sale tests in the Cheyenne market.

From test to fixed, and where we cover

Step 1: test in winter with the house closed, using a free state kit if available. Step 2: at 4 pCi/L or more, get two bids from NRPP- or NRSB-certified mitigators.

Step 3: compare them with the calculator. Step 4: retest after installation.

We cover Cheyenne, Pine Bluffs, Burns, Albin, Carpenter, Hillsdale and the Ranchettes area north of Cheyenne, along I-25, I-80 and US 85.

Communities: Cheyenne, Pine Bluffs, Burns, Albin, Carpenter, Hillsdale, Ranchettes

Before you sign

Radon calls for a planned fix after a confirmed test, not a same-day decision (EPA Citizen's Guide). Compare two written bids from certified mitigators.

Questions about Laramie County

Is radon high in Cheyenne?

EPA rates Laramie County Zone 1, a predicted average above 4 pCi/L, like 21 of Wyoming's 23 counties.

Does Wyoming license radon mitigators?

No; the Wyoming Department of Health recommends NRPP or NRSB certification.

Where do I get a free test kit in Wyoming?

The Wyoming Department of Health offers free kits to residents while supplies last.

What does mitigation cost in Laramie County?

HomeGuide's national range for a sub-slab system is $1,200 to $2,000.

Sources

Rules and fees change; confirm with the state radon office. Price your own system with the radon mitigation cost calculator, read the radon mitigation cost guide, or check any ZIP with the radon levels by ZIP tool.