City, Boone County, Illinois
Radon Testing in Belvidere, IL
Updated
IEMA has 840 radon test results on record for Belvidere. 47.9% came back at or above the EPA's action level of 4.0 pCi/L. That is close to the Boone County rate of 49.8%. A standard test runs $150 to $300. The only way to know about one specific house is to test it.
Belvidere sits east of Rockford in Boone County, the furthest regular stop in the service area. It's a mix of older in-town housing and newer subdivision builds on the edges, and both carry the same regional radon risk.
What IEMA's radon test records show
Look past the median to the tail: 1.5% of Belvidere tests were 20 pCi/L or more, five times the action level. The top reading on record is 47 pCi/L. The average result in Belvidere is 5.05 pCi/L, against 5.22 for Boone County overall. IEMA's own dataset covers tests licensed measurement professionals submitted from 2003 through July 2019, keeping only the highest reading on record per address. That means it is not a random sample and not year-by-year, but it is the closest thing to primary local radon data that Illinois publishes.
| Tests | Avg pCi/L | 4+ pCi/L | 10+ | 20+ | |
|---|---|---|---|---|---|
| Belvidere | 840 | 5.05 | 47.9% | 11.8% | 1.5% |
| Boone County | 1,628 | 5.22 | 49.8% | 12.4% | 2.1% |
Source: IEMA radon test records, Illinois Emergency Management Agency.
The ground under Belvidere
East of Winnebago County, Boone County shares the same underlying bedrock: Ordovician and Silurian dolomite and limestone, buried under glacial till left by the last Ice Age. That geology puts Boone County in the EPA's Radon Zone 1 too, the agency's highest-potential classification.
Housing in Belvidere
Census Bureau, American Community Survey 2020 to 2024 5-year estimates.
| Homes (housing units) | 9,994 | 20,291 in Boone County |
| Median year built | 1976 | 1986 countywide |
| Built before 1980 | 62.4% | 54.2% countywide |
| Attached (rowhome, townhouse) | 7% | 5.4% countywide |
| Mobile homes | 9.4% | 6% countywide |
| Renter-occupied | 29.1% | 18.2% countywide |
22.5% of homes in Belvidere were built before 1940, against 17.4% county-wide. Houses that old usually sit on stone or early block foundations with plenty of joints for soil gas to move through. That does not mean they cannot be tested and fixed, just that a mitigation contractor may need more than one suction point. 9.4% of homes here are mobile or manufactured homes. Those sit over a crawlspace or skirted pad rather than a basement, which changes how a mitigation system is built if one is ever needed. With 29.1% of Belvidere's housing renter-occupied, landlord testing questions come up often. There is no Illinois requirement to test a rental, but plenty of owners do it between tenants when the unit sits empty anyway.
Areas we cover in Belvidere
- Deer Woods
- Deer Woods II
- Oak Hills
- Morehead Meadows
Not on the list? The whole of Belvidere is covered. These are just the areas that come up most.
What we do in Belvidere
Radon testing, Radon mitigation, Buying or selling a home, and New construction.
Full pricing, the complete service menu, and the rest of the service area are on the radon testing in Rockford, IL homepage.
Common questions
Is radon a problem in Belvidere?
Yes. Out of 840 IEMA-recorded tests taken in Belvidere, 47.9% came in at 4.0 pCi/L or higher, the EPA's action level. That fits Boone County's overall Zone 1 rating, the agency's highest-potential class.
What is the highest radon reading on record near Belvidere?
47 pCi/L, out of 840 IEMA-recorded tests. That is an outlier, not typical, but it shows why testing rather than guessing matters: neighboring houses can differ by a wide margin.
I rent in Belvidere. Can I get my unit tested?
Nothing in Illinois law stops a tenant from asking for a radon test, and plenty of landlords in Belvidere test between leases anyway, since an empty unit is the easiest time to do it.
Nearby
Cherry Valley (50.2% of tests at 4+ pCi/L), Poplar Grove (58.1% of tests at 4+ pCi/L), Capron (68.6% of tests at 4+ pCi/L), Rockford (36.8% of tests at 4+ pCi/L), Bonus Township, Spring Township.
Need radon testing booked in Belvidere?
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