How Do You Remove Radon From Your Home? A Plain Guide
Discovering elevated radon is unsettling, but the good news is that radon is one of the most fixable hazards a home can have. You cannot “remove” radon from the soil — it is constantly produced as uranium decays underground — but you can keep it out of your living space and vent what enters before it builds up. The reliable method is a mitigation system that intercepts soil gas and exhausts it outdoors. This guide explains how you remove radon from your home, which methods work, and what they cost. It summarizes EPA and Colorado Department of Public Health and Environment guidance current as of 2026 and is educational only — test first and use a certified mitigator for installation.
How do you remove radon from your home?
The proven way to lower indoor radon is active soil depressurization. A pipe is installed through the foundation slab or crawl-space membrane, connected to a continuously running fan, and routed up and out above the roofline. The fan creates suction beneath the home that pulls radon gas away from the foundation and exhausts it outdoors, where it disperses harmlessly. Done correctly, this approach routinely cuts radon by 80 to 99 percent and brings most homes well below the EPA’s 4.0 pCi/L action level.
Sealing cracks and openings alone is not enough. The EPA is explicit that caulking by itself rarely lowers radon adequately, because gas finds new paths. Sealing supports a fan-driven system but is not a standalone fix. For a wider look at the options, see our overview of how to remove radon from a home.
The reason depressurization works so well is that it reverses the pressure relationship between the soil and the house. Normally a home is slightly under negative pressure relative to the ground beneath it, which draws soil gas inward through every crack and gap. By depressurizing the area under the foundation, the fan makes the sub-slab zone the lowest-pressure space, so gas flows into the pipe and out rather than into the living area. That is why a single well-placed suction point can protect an entire home, even though you have not sealed every possible opening.
Why removing radon matters in Colorado
Radon is a colorless, odorless radioactive gas. The EPA identifies it as the second-leading cause of lung cancer overall and the leading cause among people who have never smoked. Risk accumulates with years of exposure, so the sooner levels drop, the better.
The Front Range sits in EPA Radon Zone 1, the highest-risk tier, where the predicted indoor average exceeds 4.0 pCi/L. Many Colorado homes test high regardless of age or condition, which is why testing and, when needed, mitigation are standard parts of homeownership here rather than rare exceptions.
The main radon removal methods
The right system depends on your foundation. Most homes use one of these.
Sub-slab depressurization
For homes with a basement or slab-on-grade foundation, a suction pipe is set into the gravel or soil beneath the concrete slab. The fan depressurizes that layer so radon flows into the pipe instead of up through cracks. This is the most common and effective method. Our guide to reducing radon levels in a basement walks through it step by step.
Sub-membrane depressurization
For crawl spaces, a sealed plastic membrane covers the soil floor, and the fan draws from beneath it. The membrane substitutes for a slab, creating the surface the fan depressurizes.
Radon in water
Homes on private wells can have radon dissolved in the water, which releases into the air during showers and washing. Aeration or granular activated carbon treatment at the point of entry addresses waterborne radon, a separate issue from soil gas that affects some Front Range well owners.
Supportive sealing and ventilation
While sealing alone does not solve the problem, it plays a supporting role. Caulking obvious slab cracks, covering the sump pit, and sealing gaps around pipe penetrations reduce the volume of air the fan must move, making the depressurization system more efficient. Some homes also benefit from improved ventilation as a supplement, though the EPA cautions that ventilation by itself is rarely a complete fix. The dependable core remains the fan-and-pipe system; sealing and ventilation make it work better, not instead of it.
What to expect during a removal project
For homeowners who have never been through it, the process is more straightforward than it sounds. It begins with a test that confirms elevated radon and sets a baseline. A certified mitigator then inspects the home, identifies the foundation type and likely entry points, and may run a diagnostic to gauge how readily air moves beneath the slab. That visit informs the system design and the fan selection.
On installation day, the crew cores a hole through the slab or sets the membrane suction point, runs the pipe up and out above the roofline, mounts and wires the fan outside the living space, and seals the major openings. They mount a manometer on the pipe so you can see the system is pulling suction. After the fan has run, a post-mitigation test verifies the result. The homeowner is left with a quiet, low-energy system and documentation showing the home now reads below the action level.
What radon removal costs
A typical residential mitigation system is a mid-range home expense, with the exact figure driven by foundation type, the number of suction points, fan size, and routing. Crawl-space systems generally cost more than basement slab systems because the membrane is labor-intensive. Waterborne radon treatment is priced separately and depends on the equipment chosen.
Ask for itemized bids that separate the fan, piping, sealing, electrical, and post-installation testing, and get more than one quote. Local pricing varies, and our breakdown of radon mitigation cost in Colorado helps Front Range homeowners gauge whether a bid is fair.
What you can and cannot do yourself
Homeowners can handle the testing side and some supportive sealing — caulking obvious slab cracks and sealing a sump cover, for instance. But designing and installing a depressurization system that actually performs is specialized work. Fan sizing depends on soil permeability, pipe routing must avoid pulling radon back indoors, and the exhaust must terminate at a safe height. A poorly built system can fail quietly, leaving a family exposed while looking finished.
Because of that, the EPA and state programs recommend certified professionals for installation. The cost difference between a proper system and a botched do-it-yourself attempt is small next to the health stakes.
How long radon removal takes
The physical installation of a typical residential system is often completed in a single day. A crew cores a hole through the slab, sets the suction point, runs the pipe, mounts and wires the fan, and seals the penetrations. More complex homes — multiple foundation types, several suction points, or difficult crawl spaces — can take longer, but most homeowners are not without their home for any meaningful time.
The longer part is verification. After installation, the fan should run for at least 24 hours before a post-mitigation test, and a longer confirmation test gives added confidence. From the homeowner’s perspective, the timeline is usually a one-day install followed by a short waiting period for the clearance result. That quick turnaround is part of why radon is considered one of the most manageable home hazards once it is identified.
What does not work for removing radon
Several popular ideas do little on their own. Houseplants do not meaningfully reduce indoor radon. Tabletop air purifiers and HEPA filters capture particles but do not remove a gas like radon at the source. Simply opening windows lowers levels temporarily, but the moment you close up for winter, radon climbs right back, so ventilation alone is not a durable fix in a Colorado climate.
Painting or sealing the basement floor with ordinary coatings is another common misconception. While sealing visible cracks supports a mitigation system, no coating stops radon from finding the countless tiny paths through a slab and foundation. The EPA is clear that sealing by itself is not a reliable standalone solution. Recognizing what does not work saves homeowners from spending money on half-measures while the real exposure continues.
Confirming the radon is gone
Removal is not complete until a test proves it. After the fan has run at least 24 hours, a post-mitigation radon test verifies the system brought levels below 4.0 pCi/L. Reputable contractors include this clearance test. A continuous monitor offers ongoing assurance and flags any future fan failure.
Re-test every two years and after major renovations, foundation repairs, or new construction nearby, since these can change how soil gas moves. The manometer on the pipe should always show suction; a flat reading means the fan has stopped and radon protection has ended.
Keep all documentation in one place: the pre-mitigation test, the system design, the post-mitigation result, and the fan warranty. This paperwork serves two purposes. It gives you a maintenance baseline to compare future tests against, and it reassures a future buyer that the home’s radon has been measured and controlled rather than ignored. In a Zone 1 market like the Front Range, a documented, verified system is a genuine selling point.
Removing radon in different foundation types
The right removal method follows the foundation. A full basement or slab-on-grade home uses sub-slab depressurization, with the suction point set into the gravel beneath the concrete. A crawl-space home uses a sealed membrane and sub-membrane depressurization. A home with a mix — say a basement under part of the house and a crawl space under an addition — may need a combined approach, sometimes with more than one suction point tied into the same system.
Older homes with stone or block foundations, or with a sump pit, present their own wrinkles. Block walls can be hollow and carry radon upward, sometimes requiring the system to draw from the wall cavities, and an open sump is a major entry point that must be sealed and often incorporated into the suction. These variations are exactly why a certified mitigator evaluates the specific foundation before designing the system rather than applying a single template to every house.
Radon removal as a routine Front Range step
For Colorado homeowners, radon removal is best viewed as a normal part of owning a home rather than an emergency. The entire Front Range sits in Zone 1, so elevated readings are common and the fix is well understood. Treating mitigation like any other maintenance project — get a test, gather bids, hire a certified pro, verify the result — removes much of the anxiety a high reading can cause.
The payoff is durable. A properly installed system runs quietly for years on minimal electricity, protecting everyone in the home from a leading cause of lung cancer. Compared with the open-ended risk of leaving elevated radon unaddressed, a one-time installation and a small ongoing power cost is a straightforward trade. Once it is done and verified, radon moves from a worry to a solved problem, checked only by an occasional re-test.
When to call a professional
Call a certified radon mitigator when a test reads 4.0 pCi/L or higher, when buying a home with elevated levels, or when an existing system is not holding radon down. In Colorado, choose technicians certified through AARST-NRPP or NRSB, and require a written post-mitigation test as proof of performance. Pair installation with an independent confirmation test where possible so the all-clear is not coming solely from the company that did the work.
References
- A Consumer’s Guide to Radon Reduction — U.S. Environmental Protection Agency
- Radon Mitigation Information for Colorado — Colorado Department of Public Health and Environment
- Health Risk of Radon — U.S. Environmental Protection Agency
A high radon reading is fixable, and the first move is a clear plan. Reach out through our contact page and we’ll connect you with a certified Front Range mitigator who can size and install the right system for your foundation.