Radon and Real Estate: What Buyers and Sellers Need to Know
What is Radon?
Radon is an invisible, odorless, and radioactive gas that naturally occurs in the ground. It seeps into homes through foundation cracks, gaps in construction materials, and openings in plumbing systems. Radon is a byproduct of uranium decay, and its levels can vary depending on the type of soil and rock beneath a home.
Why is Radon Dangerous?
Radon is a significant health risk because it is highly carcinogenic. It is the second leading cause of lung cancer after smoking, contributing to over 3,000 deaths annually in Canada. Long-term exposure to elevated radon levels increases the risk of lung cancer, even for non-smokers.
Where is Radon Found?
Radon can be found in any home, but levels vary even between neighboring houses. It typically accumulates in basements and lower levels of homes, but it can also rise to higher floors in apartment buildings due to the "stack effect." Certain geographic areas have a higher likelihood of elevated radon levels, and home construction materials and techniques can also influence radon accumulation.
How Can You Test for Radon?
You can test for radon using commercially available radon test kits. The most reliable test takes at least 90 days and is best conducted during the winter when homes are sealed. Short-term tests are available but tend to be less accurate. Professional radon testing services are also an option for homeowners who want precise results.
What Are Safe Radon Levels?
Radon levels are measured in becquerels per cubic meter (Bq/m3) or picocuries per liter (pCi/L).
- The World Health Organization (WHO) recommends taking action at 100 Bq/m3 (or about 3 pCi/L).
- In the U.S., remediation is required at levels of 4 pCi/L (or 148 Bq/m3).
- Health Canada advises remediation within two years for levels over 200 Bq/m3 and within one year for levels over 600 Bq/m3.
How Can Radon Be Reduced in a Home?
If radon levels are too high, mitigation measures can lower them. Options include:
- Sealing foundation cracks and openings.
- Installing a sub-slab depressurization system, which vents radon gas outside.
- Improving home ventilation, especially in basements.
- Using heat recovery ventilation systems.
New homes built in British Columbia as of March 2024 must have a radon vent pipe installed to help reduce radon accumulation. However, homeowners may need to install a fan system for additional protection.
What Should Buyers and Sellers Know About Radon?
- Sellers are encouraged to disclose any radon testing and results in the Property Disclosure Statement (PDS).
- If radon levels above 200 Bq/m3 have been detected, sellers' agents are required to disclose this information to potential buyers.
- Buyers should check whether a home has been tested for radon and, if results are high, consider options like negotiating a price reduction, requesting remediation, or holding back funds for testing.
- Because radon testing takes at least 90 days, most buyers will not have time to conduct a full test before purchasing a home. However, they can ask home inspectors or radon professionals for an assessment of potential radon risks.
Final Thoughts
Radon is a serious but manageable health risk. Whether you are buying or selling a home, being informed about radon testing, mitigation, and disclosure requirements can help ensure a safer living environment. If you have concerns about radon levels in a home, consult a qualified radon professional for testing and mitigation advice.