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What are a homebuyer's options when the radon test comes back high (4.0 pico-curies/liter or more)?

Thursday, July 12, 2018

You have several alternatives when your radon test results are at or above the 4.0 pico-curies/liter line where the Environmental Protection Agency recommends remediation. Here’s our list, with the first one being the easiest:

  1. Retest - Radon levels vary from hour-to-hour throughout the day, seasonally, and also change with the weather. If your test result is just slightly over 4.0, it is acceptable to retest and use an average of the two tests. So, a 4.6 initial test and a second test at 3.0 would average out to 3.8—within the EPA acceptable range. As the original test number approaches 8.0, however, your likelihood of getting an average below 4.0 diminishes rapidly. Because it is to the seller’s benefit to have an acceptable radon test result, it is often possible to get the seller to order and pay for a second test for averaging before proceeding to mitigation considerations.
  2. Ask the seller to install radon mitigation - Under Florida law, as in many states, the seller of a residential property has an obligation to disclose all known facts that materially affect the value of the property being sold and are not readily observable. Once it has been determined that the home has an elevated radon level, if it is not mitigated and the home is not sold, then the seller must disclose the problem to all future potential buyers. This is an incentive for the seller to lower the radon level in the home, either by paying the full cost of a mitigation system or splitting the cost with the homebuyer. 
  3. Install radon mitigation yourself - The typical cost in our area is between $2,500 and $5,000, depending on the size of the home. 
  4. Decide to live with the high radon level - If the radon level is barely above the actionable level of 4.0, you might consider ignoring the EPA safety guidelines and living with the elevated radon. This is not a great idea, and not just because of the increased risk of lung cancer.  You will be required to disclose the radon problem to any potential buyers (under the Florida’s disclosure law, as noted above) when it’s time for you to sell the house, and this will make it difficult for sell without installing a mitigation system later. So you might end up installing a radon mitigation system to sell, but not receiving the benefit of having one while you are living in the home.

    For more information about radon we recommend that you visit the U.S. Environmental Protection Agency’s radon homepage at

    Also, see our blog post Can a radon test result be wrong? and Can the seller tamper with a homebuyer's radon test to change the results?

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Here’s links to a collection of our blog posts about “RADON":

 Is a radon mitigation fan required to be on a dedicated circuit breaker/fuse in the electric panel?

What happens to a radon test result if the windows were opened, the test device moved, or there was any other evidence of tampering during the test? 

Where do I find the Florida laws regarding radon?

Can I test vacant land for radon before building a house? 

Is radon mitigation possible for a condominium?

Do radon mitigation systems require maintenance?

What is the average life expectancy of a radon mitigation system?  

Do older houses have higher radon levels than new houses? 

Can the seller tamper with a homebuyer's radon test to change the results?

How long does it take to get the results of a radon test? 

Will opening the windows reduce the radon level in a house?

How was it determined that between 15,000 and 22,000 lung cancer deaths each year are caused by radon?

Can a homebuyer do their own radon test for a real estate transaction with a self-test kit?

What is the danger of radon in well water

For how many years does an old radon test result remain valid?

Should homeowners get a pre-listing radon test before selling their home?

What are a homebuyer's options when the radon test comes back high (4.0 pico-curies/liter or more)? 

Do granite countertops emit radon?

How can I tell if a house has a radon mitigation system? 

Can a mobile/manufactured home have a high radon problem?

Do I need to test for radon when buying a condominium? 

What does a radon mitigation contractor do to lower the radon level in a home?

How can not testing for radon be an expensive mistake for homebuyers? 

Will the radon test come back sky-high in a house that has been empty and closed-up for months? 

What is radon? Should I be concerned about it?

Should I buy a house with a high radon level? 

What is the average radon level of indoor and outdoor air in America?

What is the operating cost of a radon mitigation system? 

• Should I buy a house with a radon mitigation system?

• Does the buyer or seller of a home pay for radon mitigation when the radon test comes back high? 

• What is the probability of having high radon in a Florida house?

• How quickly do I need to reduce a high radon level in my house? 

Does a home inspector check for radon?

What are the problems with underground return air ducts? 

• What is the probability of having high radon in a Florida house?

• What factors can change radon test levels up or down?

    Visit our RADON page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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