Frequently Asked

About Radon Mitigation Systems

How much do radon mitigation systems cost?
The cost of a system varies depending on a number of factors, but they typically cost between $900-$5,000 per building. To learn more about our pricing, click here.
How does radon mitigation work?

Radon mitigation systems typically suction radon gases out before they enter the home. To learn more about how radon mitigation works, click here.

Are radon mitigation systems guaranteed to work?

Yes, but different companies give different guarantees. To learn more about system guarantees, click here.

How long is the installation time?
Most systems can be installed in a couple of days. DuPage Radon Contractors has a large team that can install nearly every system in only one day. To learn more about our installation process, click here.
How do I know the system is working?

There is a gauge, called the u-tube, that indicates if the system is operating. However, this gauge does not measure radon, so you will need to secure a radon test after installation. State law does not allow DuPage Radon Contractors to test its own systems, but you can read our resource on radon testing here to find out more about your test options.

What if I want my test results to be under 4 pCi/l?

We usually can get radon levels lower than 4 pCi/l if requested. Typically, we install our standard system and see where the retest levels are. Quite often, they retest below 2 pCi/l. However, if test results occur between 2 and 4, we can usually do additional work to lower it further. Because of the inability to see what is happening under the floor, we seldom guarantee to get results under 4pCi/l.

Can’t I just seal the cracks and sump cover?

Sealing the cracks is part of a passive system approach. These systems have been proven to have very limited effectiveness, in part because soil gasses can penetrate concrete floors.

Why do I need more than one suction point?

Radon gas is removed using suction running through the gravel under the concrete floor or membrane. Some older homes have dirt under the floor instead of gravel, and so more suction points are needed as the suction does not spread as far. In addition, gravel under a basement floor does not connect to the gravel in a crawlspace or slab-on-grade, and so a separate suction point is needed for each part of the lowest level.

Why do I need a suction point in an area that tested OK?

State regulations say that if one area (basement, crawlspace, or slab-on-grade) fails a test, a radon mitigator is required to install a suction point in all areas. This is because radon levels can fluctuate over the years, so addressing all areas enables the owner to feel comfortable that he or she is unlikely to have further radon issues.

Why is my system a different price than my neighbor’s?

Radon mitigation systems need to be custom-designed to the building, so prices change depending on the challenges. Even homes with the same first floor layout may have differences in the basement or crawl space and thus different pricing. Learn more about the factors that can affect radon mitigation pricing here.

What keeps rain and debris out of the top of the discharge?

Per state statute, the tops of all discharges are open to the sky. This is to avoid accumulation of ice in the winter that can close the opening.  The wind of the exhaust keeps most leaves and debris out. Any water that may enter is channeled through the piping to the substrate where it heads toward the sump pump.  On a very rare occasion large debris or a squirrel can enter the discharge and may need to be removed.  

Why don’t you offer a lifetime warranty?
The promise of a “lifetime guarantee” often comes with several exceptions that leave out key system components, or they only cover the parts of the system that are inherently long-lasting. In short, a “lifetime guarantee” isn’t always the best deal – sometimes you’re better off with a warranty that covers the important things. Learn more about DuPage Radon Contractors’ warranty here.
Why don’t you put the suction into the sump?

Installing the main suction point into the sump pit is a practice that used to be employed but is no longer allowed by state regulations. Only a secondary pipe can enter the sump pit. The change was made because sump pit suction pipes are more prone to being disturbed by sump pump repair people.

About Radon Testing

Who should test for radon, and where is radon found?
All parts of northern Illinois have high radon. Some locations range from 1 in 4 buildings testing for high radon to nearly every building containing high radon levels in some areas. Everyone living in a free-standing home should test. In multifamily situations, condos, and townhomes, all units on the first or second floor should test. Read more about radon testing here.
How often should I test for radon?

It is recommended that you test for radon every 2 years.

Can I use a home radon test?

Real estate transactions usually require professional testing. Home tests are available however and usually cost $35-$65 with lab fees, and are available at local hardware stores and home centers. Professionals cost about $100-$300 a building. Learn more about radon testing and find a licensed professional tester here.

What is an acceptable radon level?

4 pCi/L or above is the action level set by the EPA, and is the level most used for real estate transactions. The World Health Organization uses an action level of 2.7.

How high is my number?

A handy refence benchmark is the level of radon that you might experience while walking outdoors in northern Illinois, which usually ranges from below .5 to 2pCi/l. Radon levels in northern Illinois over 50 are very rare, while levels over 25 are considered very high and levels under 10 are the most common.

Does a vacant, closed-up house test higher?

Sometimes, but not always. Sometimes they test slightly lower than they would have had people been coming and going. Either way, it is not usually enough to make a big difference in the final number.

Does the weather affect the test?

Weather can affect a radon test, but usually only minimally. If you’re concerned about weather impacting your test results, hire a professional tester. Professionals know when to alter their procedures due to severe weather conditions.

How long does a new mitigation system need to run before retesting?

It is recommended that you let the system run for a minimum of 24 hours before retesting.

Do I really have to retest?

It is worth having the retest performed, simply because some of the assumptions about under-slab conditions that go into the design of the system do not always operate as designed. Even the best radon mitigators have systems that don’t work as hoped. DuPage Radon Contractors has a very high first-attempt pass rate at 99.6%, but you would hate to be in the small percentage that fail and live with the false belief that your radon issue has been solved.

What if the system fails the retest?

We will come perform some diagnostics and make changes to the system. These changes may include increasing the size of the fan, adding more suction points, or other adjustments. If you have our standard warranty, these adjustments are all free to you. We will also pay for your next retest to ensure we got it right.

System Repair & Maintenance

How much work is required to maintain the system?

Very little. Just check the u-tube weekly if you don’t have an alarm. Replace the fan whenever it wears out, usually in 7-12 years.  

How long do fans last?
Fans can last anywhere from 1 year to 25 years, but most last 7 to 12 years. Learn more about fan repair and replacement here.
How much electricity does a radon mitigation system use?

Most systems use about 60-70 watts. This equates to about $30-60 a year in electricity costs.

How do I know my system is working?

There is a gauge that indicates if the system is operating. Learn how to read this gauge here.

What does the gauge on the pipe tell me?
This gauge is called a u-tube. It detects if the system is creating suction. It does not measure radon levels. Learn how to read this gauge here.
The line next to the u-tube does not line up with the liquid. Now what?

Any hand-drawn line on your gauge was an indicator to the installer. If the gauge has moved, it is not important to the operation of the system as long as the two sides of the liquid are not level. However, if the u-tube is obviously broken or missing any liquid, please call us.

How do I get into my sump pit?

If you are just interested in observing the operation of the pump, most of our covers have a clear window through which you can see using a flashlight. If you need to remove the cover, loosen any screws that connect it and pry it upwards to break the caulk bond. When you are finished in the sump pit, reinstall the cover using caulk to make for an airtight seal. Restoring the airtight seal is critical - if you do not seal it, the system may not work properly. If you have concerns about doing this correctly, feel free to contact us and we’ll be happy to walk you through the process. We can also remove and replace the cover for you for $169, including the trip charge.

What type of caulk do you use?

Since caulk is not designed to stop radon, most good caulks can be used. We typically use Geocel 2000 and Big Stretch, both which are available at local stores or online.

The plastic membrane in my crawl space is billowing up. What’s going on?

Under certain weather conditions, the soil gases come up from the soil faster than the system can evacuate it. If this is an occasional event, it is usually harmless and the system will eventually catch up. However, if this is a constant state for your system or if the membrane looks as if it will pop or explode if not released, contact us.

What is the gurgling noise in my pipes?

The gurgling noise is typically caused by the movement of water within the pipes as air rushes by it. If it is an occasional noise, it is usually harmless and the air past the water may soon help the water evaporate. If the noise persists for several weeks, contact us

What is that whistling noise my radon system makes?

The whistling noise is typically caused by an air leak in the mitigation system. It is usually a small leak which is unlikely to affect the system dramatically. If you find the hole and are handy, you can caulk it yourself. However, we can come out and fix it if needed.


What is the grinding noise my radon fan has started to make?

This is could be a fan whose bearings are going bad. Fans typically last 7-12 years. It could also be debris in the fan blades. Contact us to provide an evaluation

About Radon

What is radon?
Radon is a radioactive, odor-less, taste-less gas. It comes from the natural decay of radium in the soil that can enter through cracks or through the concrete of a building. Learn more about radon and what causes it here.
How is radon dangerous?
When inhaled, the particles in the gas change DNA in the lungs. Over the course of years, this can dramatically increase your odds of developing lung cancer. Radon is the second leading cause of lung cancer and kills more people than drunk driving, causing over 1,000 deaths per year in Illinois alone. Learn more about the dangers of radon here.
Where is high radon found in our area?

All parts of northern Illinois have high radon levels. High radon levels can be found in anywhere from 1 in 4 buildings to nearly every building in some areas of this region. Because of the high occurrences of radon in this area, it is important that you test for radon every two years.

How much is too much radon?

4.0pCi/L or higher is the action level set by the EPA, and is the highest amount acceptable for any real estate transactions in Illinois. The World Health Organization uses 2.7 as their action level. However, like x-rays, all levels of radon are considered potentially harmful. Learn more about radon’s effects here.

Still have questions for the DuPage Radon Contractors team? We’re happy to answer any further radon mitigation or testing questions or concerns you may have. Send us some information or give us a call today and we’ll offer our expertise.

What Our Customers Say