Iowa has the highest average indoor radon levels in the nation, and roughly 7 in 10 Iowa homes test at or above the EPA action level of 4.0 pCi/L. Johnson County sits in EPA Radon Zone 1, the federal designation for areas with the highest radon potential. If you live here and have never tested your home, the odds are genuinely not in your favor.
We provide professional radon testing and radon mitigation across Iowa City, Coralville, North Liberty, Tiffin, Solon, University Heights, and the rest of Johnson County. Our technicians are certified through the Iowa Department of Health and Human Services state radon program, as Iowa law requires for anyone doing this work professionally. Radon is what we do, all day, in the same soil and housing stock you live in.
Whether you are buying or selling a home, renewing a rental permit under Iowa City's radon ordinance, or simply want to know what your family is breathing, everything starts with a measurement. Radon is colorless, odorless, and tasteless. Testing is the only way to know.
Our Services
Radon Testing
Professional radon testing in Iowa City and Johnson County with calibrated continuous monitors and clear, documented results.
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Radon Mitigation
Radon mitigation systems for Iowa City area homes, installed in a day and verified by retest, typically bringing levels under 2.0 pCi/L.
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Real Estate Radon Testing Urgent
Certified radon testing for Iowa City home sales, with results delivered inside your inspection window.
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Rental Property Radon Compliance
Radon testing and mitigation for Iowa City rental permits, handled end-to-end for landlords and property managers.
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Radon System Repair & Maintenance
Radon mitigation system repair, fan replacement, and annual checkups for Iowa City and Johnson County homes.
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Commercial & Multifamily Radon Services
Radon testing and mitigation for apartments, offices, schools, and commercial buildings across Iowa City and Johnson County.
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Why Iowa City Homes Have a Radon Problem
Radon is a radioactive gas produced by the natural decay of uranium in soil, and Iowa's glacial soils carry an unusual amount of it. As glaciers ground rock into the fine-grained deposits our region is built on, they left uranium-bearing material spread evenly under nearly every lot in Johnson County. That geology is why the EPA places the entire county in Zone 1, its highest-risk category.
The gas moves up through the soil and into buildings through whatever openings it finds: sump pits, floor drains, cracks in the slab or foundation walls, gaps around plumbing penetrations, and exposed dirt in crawl spaces. Because a heated home operates at slightly lower pressure than the soil beneath it, the house actually pulls radon in. It does not need a big opening — hairline cracks are enough.
No style or age of home is exempt. We measure elevated radon in pre-war houses near downtown, the Northside, and Longfellow just as often as in brand-new construction in North Liberty and Tiffin. New homes are often tighter, which can trap radon more effectively. And because soil conditions vary lot to lot, your neighbor's test result tells you almost nothing about your own.
The Health Stakes Are Real
Radon is the second-leading cause of lung cancer overall and the leading cause among people who have never smoked. The EPA attributes about 21,000 lung cancer deaths in the United States to radon every year. Those numbers are not scare tactics — they are the reason the EPA, the Surgeon General, and the State of Iowa all recommend testing every home.
The danger comes from time. Radon exposure causes no headaches, no coughing, no symptoms of any kind while it is happening, so families can breathe elevated levels for decades without a clue. The risk accumulates with years of exposure, which is exactly why finding out now matters more than finding out later.
The encouraging part is that this is a completely solvable problem. Radon levels can be measured accurately in two days and reduced dramatically in one. Few risks of this size can be fixed that quickly, at a known cost, with a verifiable result.
Testing: When You Need It and How It Works
Our radon testing service uses a continuous radon monitor, or CRM — a calibrated professional instrument that records radon levels hour by hour instead of producing a single blended number. The standard measurement runs a minimum of 48 hours under closed-house conditions, meaning windows stay shut and doors are used only for normal coming and going. The hourly data also reveals tampering and unusual swings, which matters when the result carries legal or financial weight.
You need a test if you have never had one, and you should retest about every two years even with a previous good result, since soil gas and homes both change. Test again after finishing a basement, replacing HVAC equipment, adding an addition, or repairing a foundation. And if you already have a mitigation system, periodic retesting confirms it is still doing its job.
Real estate transactions are the other big trigger. Our real estate radon testing is built around inspection-period deadlines, with prompt scheduling and same-day reporting once the measurement ends, so buyers, sellers, and agents get a defensible number in time to negotiate with it. Professional testing in our area typically runs about $150 to $250 — small money compared to what the answer is worth.
Mitigation That Actually Works
When a home tests at or above 4.0 pCi/L, the fix is radon mitigation by active sub-slab depressurization, the method proven over decades of use. We core a small suction point through the basement slab, connect it to a sealed pipe run, and install a continuously running fan that vents soil gas above the roofline. Instead of your house pulling radon in, the system pulls it out of the ground before it ever reaches your living space.
A properly designed system typically brings indoor levels under 2.0 pCi/L — not just below the action level, but well below it. Most residential installations in the Iowa City area cost between $900 and $1,400 and are completed in a single day. Sealing sump pits, floor drains, and slab cracks is part of the work, because a tight slab lets the fan do its job efficiently.
Every installation ends with a post-mitigation verification test. You do not have to take our word that the system works; the follow-up measurement proves it with a number.
Landlords, Buyers, Sellers, and Property Managers
Iowa City landlords face a legal requirement, not just a recommendation. The city's rental ordinance, effective July 1, 2021, made Iowa City the first city in Iowa to require radon testing for single-family and duplex rentals — and mitigation whenever results come back at 4.0 pCi/L or higher — tied to the rental permit cycle. Our rental property radon compliance service handles the whole obligation: testing on your permit schedule, mitigation where needed, and documentation ready for the city.
Sellers have obligations too. Under Iowa Code chapter 136B, home sellers must disclose known radon test results and any mitigation efforts. In practice, testing before you list — and mitigating if needed — turns radon from a last-minute negotiation problem into a selling point you control.
Larger properties are a different job, and we are set up for it. Our commercial and multifamily radon services cover apartment buildings, offices, schools, and HUD multifamily testing, which follows its own protocols for unit sampling and documentation. If you manage buildings anywhere in Johnson County, we can build a testing plan that satisfies the standard that applies to you.
Why Certified Local Professionals Matter
In Iowa, radon measurement and mitigation professionals must be certified through the state radon program run by the Iowa Department of Health and Human Services. That certification is your baseline protection: it means trained technicians, calibrated equipment, and accountability to state standards. Ask anyone who offers to test or mitigate your home for that credential — we gladly show ours.
Local experience matters just as much. Mitigating a century-old house in the Northside with a stone foundation and a dirt crawl space is a different project than a new build in Tiffin with a passive rough-in already in the walls. We design each system around the actual foundation in front of us, not a one-size-fits-all diagram.
We also stand behind systems for the long haul, including ones we did not install. Our radon system repair and maintenance service covers fan replacement, manometer checks, re-sealing, and diagnosing systems that have quietly failed. A mitigation system with a dead fan is just a pipe — if your manometer reads level or you have not looked at it in years, have it checked.
Our Process, and Where We Work
The process is simple. Call us or send the form on this page, and we will schedule a test — usually within a few days, faster when a real estate deadline is involved. We place the monitor, run the 48-hour measurement, and deliver a written report that gives you your number and explains in plain language what it means.
If your result is 4.0 pCi/L or higher, we quote a mitigation system designed for your specific foundation, with the price and the target stated up front. Most installs happen within a week or two of approval and finish the same day they start. A verification test afterward confirms the system brought your level down, typically under 2.0 pCi/L, and we show you the simple monthly manometer glance that confirms it stays there.
We serve Iowa City, Coralville, North Liberty, Tiffin, Solon, University Heights, and the rest of Johnson County. If you are anywhere in the area and do not know your radon number, that is the one thing worth fixing this week. Request your test today and get the answer in about 48 hours.
Frequently Asked Questions
How much does radon testing cost in Iowa City?
Professional radon testing in the Iowa City area typically runs $150 to $250. That includes a calibrated continuous radon monitor placed in your home for at least 48 hours under closed-house conditions, plus a written report you can use for a real estate transaction or rental permit. Johnson County Public Health also sells DIY kits for around $12 to $15 — fine for casual screening, but transactions and rental compliance need a professional test.
How much does a radon mitigation system cost?
Most homes in Iowa City run $900 to $1,400 for a complete active sub-slab depressurization system, installed in a day. The price varies with foundation type — a simple basement slab is the low end, while crawl spaces needing a sealed membrane or homes needing multiple suction points cost more. Every install includes a post-mitigation retest to verify levels dropped.
What level of radon is dangerous?
The EPA action level is 4.0 pCi/L — at or above that, fix the home. But there is no known safe level of radon, and the EPA recommends considering mitigation between 2.0 and 4.0 pCi/L. For context, roughly 7 in 10 Iowa homes test at or above the action level, the highest rate in the nation.
How long does a radon test take?
A minimum of 48 hours. The home must stay under closed-house conditions — windows shut, doors closed except for normal coming and going — for the whole test so the reading reflects real conditions. We drop off the monitor, pick it up two days later, and you get results the same day.
Do Iowa City landlords have to test for radon?
Yes. Iowa City was the first city in Iowa to require radon testing in single-family and duplex rental properties, effective July 1, 2021. Testing is tied to the rental permit cycle, and if a unit tests at 4.0 pCi/L or higher it must be mitigated. We handle testing, mitigation, and the documentation the city expects.
Does radon mitigation actually work?
Yes — an active sub-slab depressurization system is proven technology. A pipe and fan create suction under your foundation so radon vents above the roofline instead of seeping into living space. Properly installed systems routinely bring homes from well above 4.0 pCi/L down below 2.0, and we verify every install with a follow-up test.
Why is radon so bad in the Iowa City area?
Geology. The glacial deposits under Iowa are rich in uranium, which decays into radon gas. That's why Johnson County sits in EPA Zone 1, the highest radon potential classification, and why Iowa leads the nation in elevated homes. Age of the home doesn't matter much — new construction in North Liberty tests high just as often as pre-war homes near downtown.
I'm buying a home — when should I schedule the radon test?
The moment your offer is accepted. The test itself takes 48 hours and inspection periods are short, so early scheduling keeps radon results from holding up your closing. If the result comes back high, mitigation is a normal negotiating item — usually around $900 to $1,400, often paid by the seller.