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Buying and selling5 min read

Does a radon mitigation system hurt resale value?

By Radon411 Editorial TeamUpdated How we research

Short answer

We know of no published figure showing that a radon mitigation system lowers resale value. Where radon problems have been fixed, home sales have not been blocked or frustrated, and a working system with test records showing low levels is sometimes a good selling point.

Next step: see how a radon test fits a home sale. Testing for a home sale

A system tells a buyer that the home once had a radon problem and that it was fixed. Buyers often ask whether a home has been tested and whether elevated levels were reduced, and a system with its records answers both.

Keep the paperwork: the test results from before the fix, the test done within 30 days of installation, later retests, and the installation contract, which should state whether any warranties or guarantees transfer if you sell. Save the test results and all information about the steps taken to fix the problem; this could be a positive selling point.

When you sell, tell potential buyers about the system and give them information on its operation and maintenance. A buyer may still ask for a new test, especially if the last one is not recent, for example within two years.

What to do next: if you are selling, gather the system's records and run a new test with the system on. If you are buying, ask for those records and consider your own test.

What a radon system tells a buyer

A radon system tells a buyer two things: the home once had a radon problem, and someone fixed it. More and more, buyers and renters ask about radon before they buy or rent, and buyers often ask both whether a home has been tested and whether elevated levels were reduced. A working system answers both questions.

A system can only help a sale if a buyer can see it works. That comes down to records and a recent test.

Records that reassure a buyer

Save the test results and all information you have about the steps taken to fix the problem; this could be a positive selling point. When you sell a home that has a radon system, tell potential buyers about it and give them information on its operation and maintenance.

The paperwork to keep for a radon system
RecordWhat it shows a buyer
Test results from before the fixHow high the level was
The post-mitigation testThat the system lowered it; this test is due within 30 days of installation
Later retestsThat levels remain low; a retest at least every two years is advised
The installation contractWhat was installed, any guarantee, and whether warranties transfer to a new owner
Operation and maintenance informationHow to keep the system running, including its warning device

Show that the system still works

A buyer may ask for a new test, especially if the last test is not recent, for example within two years, or if the home has been renovated or altered since. If you test for a sale, make sure the system is working properly and running for the entire test, and that the vent fan is operating.

Timeline after a radon mitigation system is installed: the fan runs continuously, test no sooner than 24 hours and within 30 days, then retest at least every two years.
Read this figure as text

  1. Day of installation

    The system goes in

    Keep the fan running at all times: it must run continuously for the system to work correctly.

  2. No sooner than 24 hours

    Earliest post-mitigation test

    Test no sooner than 24 hours after your system is in operation with the fan on, if it has one.

  3. Within 30 days

    Post-mitigation test done

    A two- to seven-day measurement is recommended, and EPA recommends an independent follow-up radon measurement as well as any test the contractor runs.

  4. At least every two years

    Retest

    Retest your home at least every two years to be sure radon levels remain low.

Test conditions: Windows and doors must be closed 12 hours before and during the test, except for normal entry and exit. Not drawn to scale.

After a remodel. After you remodel, retest in the lowest lived-in area to make sure the construction did not reduce the effectiveness of the radon reduction system.

Testing after a radon system goes in: the first check, then regular retests a buyer can ask to see.

The system itself helps a buyer judge it. Radon systems must be clearly labeled, and an active system must have a warning device that alerts you if it stops working properly. The fan must run continuously, and fans may last five years or more.

Warranties and the installation contract

A good installation contract carries over into the sale. It should spell out any guarantee and the warranties, and it should state whether those transfer if you sell.

Contract terms that matter at resale
TermWhy it matters when you sell
Guarantee to reduce radon below a negotiated levelShows the level the system was built to reach
Warranties on the hardware componentsCovers the fan and other parts
Whether warranties or guarantees are transferableTells a buyer whether the coverage passes to them
Optional extended warranty or service planCan add coverage a buyer values

Selling with a high result and no system

If you have not fixed a radon problem yet, the timing matters more than the system. Test your home before putting it on the market, and fix a problem if it exists so it won't complicate your sale. It is better to correct a radon problem before listing, because you have more time to address it.

A seller's radon timeline
WhenWhat to do
Before listingTest, and save the results in case a buyer is interested
If the level is highHave a system installed while there is time
After installationTest again within 30 days and keep the result
During the saleShare the records, and keep the system running for any buyer's test

A buyer may also ask for a new test if your state or local government requires disclosure of radon information to buyers. See is it hard to sell a house with radon.

Questions about radon systems and resale

Does a radon mitigation system lower home value?

We know of no published figure showing that it does, and we do not give one. Where radon problems have been fixed, home sales have not been blocked or frustrated, and the added protection is sometimes a good selling point.

Do I have to tell buyers about a radon system?

If you sell a home with a radon system, inform potential buyers and give them information about its operation and maintenance. Some states and localities require disclosure of radon information.

Does a radon system warranty transfer to the buyer?

It depends on the contract, which should state whether any warranties or guarantees are transferable if you sell your home.

Should I retest before selling a house with a system?

It helps. A buyer may ask for a new test if the last one is not recent, for example within two years, or if the home was renovated since.

Is a visible vent pipe a problem for buyers?

A radon system must be clearly labeled, so buyers will know what it is. What reassures them is the record showing it works.

Is it better to fix radon before listing?

Yes. Correcting a radon problem before placing the home on the market leaves you more time to address it.

Buying and selling

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