Radon in the Real Estate Transaction
Couple standing in front of a new home with agent.

Radon in the Real Estate Transaction

Real estate professionals play a critical role in helping customers navigate the home buying and selling process. An important part of the process is ensuring that buyers are fully aware of any hazards in the home, including radon. By learning radon basics, real estate professionals can avoid potential delays liability problems.

Encourage Early Disclosure

The Environmental Conditions portion of the Colorado Seller’s Property Disclosure Form specifically lists radon as a hazard that must be disclosed if known by the seller to exist or ever have existed. This is true even if previous test results were less than 4.0 pCi/L.

  • Sellers should provide copies of any test results.
  • Existence of a radon mitigation system must be disclosed. (It is presumed that radon existed previously, and that if the system were to fail, the radon level would return to its original level.)

Encourage Testing of ALL Homes

The source for radon entering a building is generally just beneath the building. Soil can vary from building to building, even within the same neighborhood. Therefore, the decision to test should not be based on test results from adjacent homes, zone maps, or survey maps. Instead, it’s best to encourage every buyer to test for radon.

Encourage Testing at the Time of Sale

Testing at the time of sale should be included as a normal part of the inspection process to:

  • Reduce liabilities and buyer anxieties
  • Reduce variables and interferences
  • Provide information upon which the buyer can make an informed decision

Radon concentrations vary with season and occupant behavior; however, radon tests at the time of sale identify the potential for elevated radon, regardless of the living patterns of the inhabitants. Radon professionals are trained to identify radon potential so that buyers can be reasonably confident that, if the radon potential is low, the levels will be low when the home is normally occupied and on a long-term basis. This type of testing (short-term) usually takes 2-7 days.

Use a Qualified Radon Professional

Although radon testing can be done by the homeowner, the test may be suspect if not performed by an objective third party such as a radon measurement professional. And, such professionals are trained to identify radon potential, regardless of the season or occupant behavior. Find a certified radon testing professional.

Real Estate Radon Testing Options

  • Sequential testing method involves two devices placed in the lowest potentially occupiable portion of the home for 48 hours, one after the other. The average of the two test results forms the basis for decision.
  • Simultaneous testing method involves placing two test devices four inches apart in the lowest potentially occupiable portion of the home for 48 hours. This allows the tester to safeguard against errors.
  • Continuous testing method involves a single test placed in the lowest potentially occupiable portion of the home for a minimum of 48 hours. The test must be able to report results in increments of one hour or less to identify unusual swings. Decisions are based on the average reading of the hourly reported results.

Test Results

There is no safe level of radon exposure. The average national indoor radon level is approximately 1.3 picoCuries per liter (pCi/L) of air. Homeowners should consider fixing homes between 2 and 4.0 pCi/L. Radon mitigation can be simple and inexpensive.

Radon Contingencies

When contingencies are written on radon, cite an acceptable level, such as the EPA’s action level of 4.0 pCi/L and, even before the testing is conducted, discuss whether mitigation is an acceptable method for removing the contingency.

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