Published on: May 15, 2013

If the economic pundits are correct, it looks like this Spring and Summer will see a significant uptick in unit sales and transactions throughout the region. Which means prospective buyers will be performing more unit inspections including testing for the presence of Radon gas. Accordingly, we thought we would include some information and guidance in this month’s newsletter in the event your Association experiences a gassy situation or a frantic call from a Unit Owner demanding immediate action because Radon was detected in his or her unit.

What is Radon Gas?

Answer: Radon gas comes from the natural (radioactive) breakdown of uranium in soil, rock and water, and can get into the air in units through the ground by seeping through the foundation. Sometimes Radon can enter a home through well water as well. The Surgeon General has warned that Radon gas is the second leading cause of lung cancer in the United States. The United States Environmental Protection Agency (EPA) has set an action level of 4 pCi/L for indoor spaces. At or above this level of Radon, the EPA recommends that corrective measures to reduce the level of Radon be taken.

If an Owner’s Unit tests positive for high Radon levels as a result of Radon coming into the Unit through the cement floor, is the Association responsible for mitigating the Radon?

Answer: If the concrete floor or foundation has cracks or defects, the Association would be responsible for repairing those cracks and defects. However, Radon is a naturally occurring substance that may come through the floor and foundation even if there are no defects present. The mere fact that water or air contaminated with Radon may have become trapped in the unit does not mean the Association is responsible for mitigating it. The Association cannot prevent the natural breakdown of Radon in the soil, nor would it be liable for Radon seeping into the unit because of this breakdown. As the Owner is responsible for his or her unit, he or she is responsible for remediating the Radon from the unit. However, the Board should cooperate with the Unit Owner if the Owner wants to remediate the Radon.

Does the Owner have a right to modify the common elements in order to install a Radon Mitigation System?

Answer: No, not without prior approval from the Association.

Mitigating Radon from the unit will require some form of Radon Mitigation System, which will likely require modification to the common elements of the condominium building (e.g., construction of ventilation ducts through the common elements and to the exterior of the condominium building). Most condominium documents prohibit any modification to the common elements without first obtaining the written approval from the Association. To the extent the Owner’s Radon Mitigation plan would affect or require modification of the common elements, the Association should require Owners to submit plans of the proposed mitigation system for its review, and require that the Owner to sign some form of written modification or license agreement.

Because modification to the common elements could cause additional maintenance, risk, and liability for the Association, the Board may condition its approval of the Radon Mitigation System on a variety of criteria. Some sample criteria are as follows:

  • Requiring a professional radon mitigation contractor to perform the work in conformity with applicable federal and state guidelines;
  • Prohibiting roof penetrations (where there is an alternative);
  • Requiring the unit owner to be responsible for the maintenance, repair, and replacement of the radon mitigation system;
  • Requiring camouflaging of the vent pipe so as to blend in with the exterior materials of the building.

Now that the Board is on notice that at least one unit has tested high for Radon gas, does the Board have a duty to disclose this information to the rest of the community?

Answer: While the Association may not have the legal duty to notify Owners of the presence of Radon detected in one unit, because of the potential health concerns involved, we recommend that the Board notify residents that the presence of Radon was detected in a unit, and that if they are concerned about their unit, they should have the unit tested. The Board may also want to include information to contact the EPA, and mention that the presence of Radon in one Unit does not necessarily mean Radon is present in other units.


Although generally an Owner is responsible for mitigating Radon from their unit, and the Association is responsible for mitigating Radon from the common elements, obligations for radon mitigation are both document-specific and fact-specific. Please contact our office at: (781) 843-5000 if you would like to discuss a specific issue and/or circumstance.