City, Ogle County, Illinois
Radon Testing in Rochelle, IL
Updated
IEMA has 377 radon test results on record for Rochelle. 41.4% came back at or above the EPA's action level of 4.0 pCi/L. That is below the Ogle County rate of 49.7%, though still a real share of homes. A standard test runs $150 to $300. The only way to know about one specific house is to test it.
About 9,529 people live in Rochelle, a Ogle County city with roughly 3,947 housing units and a median year built of 1971. It sits near Oregon, Byron and Mount Morris. It's the largest city in Ogle County, known locally as a rail hub where two major freight lines cross.
What IEMA's radon test records show
Look past the median to the tail: 0% of Rochelle tests were 20 pCi/L or more, five times the action level. The top reading on record is 17 pCi/L. The average result in Rochelle is 4.12 pCi/L, against 5.98 for Ogle 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+ | |
|---|---|---|---|---|---|
| Rochelle | 377 | 4.12 | 41.4% | 5% | 0% |
| Ogle County | 1,751 | 5.98 | 49.7% | 15.7% | 3.9% |
Source: IEMA radon test records, Illinois Emergency Management Agency.
The ground under Rochelle
Ogle County runs along the Rock River south of Winnebago and Boone Counties, on the same general family of dolomite and limestone bedrock, with Ordovician rock exposed in spots near the river. The EPA places Ogle County in Radon Zone 1 too, the same highest-potential category as its neighbors to the north.
Housing in Rochelle
Census Bureau, American Community Survey 2020 to 2024 5-year estimates.
| Homes (housing units) | 3,947 | 22,682 in Ogle County |
| Median year built | 1971 | 1972 countywide |
| Built before 1980 | 79.3% | 71.8% countywide |
| Attached (rowhome, townhouse) | 7.5% | 2.2% countywide |
| Mobile homes | 0% | 2.5% countywide |
| Renter-occupied | 46.9% | 24.6% countywide |
Most of the housing in Rochelle went up between the 1940s and the 1970s (79.3% was built before 1980, median year 1971). That era mostly means poured or block basements, which is the standard layout for a sub-slab test and, if needed, a sub-slab mitigation system. With 46.9% of Rochelle'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.
What we do in Rochelle
Radon testing, Buying or selling a home, and New construction.
Common questions
Is radon a problem in Rochelle?
Yes. Out of 377 IEMA-recorded tests taken in Rochelle, 41.4% came in at 4.0 pCi/L or higher, the EPA's action level. That fits Ogle County's overall Zone 1 rating, the agency's highest-potential class.
What is the highest radon reading on record near Rochelle?
17 pCi/L, out of 377 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 Rochelle. Can I get my unit tested?
Nothing in Illinois law stops a tenant from asking for a radon test, and plenty of landlords in Rochelle test between leases anyway, since an empty unit is the easiest time to do it.
Nearby
Oregon (54.5% of tests at 4+ pCi/L), Byron (50.3% of tests at 4+ pCi/L), Mount Morris (71.9% of tests at 4+ pCi/L).
Need radon testing booked in Rochelle?
Tell us why you're testing and any deadline you're working against. You get a fixed price and a straight answer back.