When buying or selling a property, people usually focus their attention on location, price, light levels… but rarely on radon. And yet, this invisible and odourless gas may be found in homes across Québec.
Is this cause for concern? Yes, but don’t panic: the situation is easily remedied.
What Even Is Radon?
It’s a natural radioactive gas that comes from uranium present in the soil. It becomes an issue when it gets into homes and accumulates there.
As it’s heavier than air, it tends to build up in the basement, namely through cracks in the concrete slab, the foundation walls, dirt floors, sumps, and crawl spaces.
In poorly ventilated zones, the gas can reach very high concentration levels, which poses a health risk.
This isn’t the case outdoors where it dissipates quickly.
What Are the Associated Risks?
Over the long term, radon represents a public health issue because it’s the second cause of lung cancer in Canada, after smoking. Hence the importance of acting, without giving in to panic.
According to Health Canada, the acceptable threshold is 200 Bq/m³. Above this level, corrective measures are recommended.
Why Have I Not Heard of Radon Before?
Probably because the phenomenon occurs rarely in Québec!
Concentration levels for most properties here are below the limit.
Furthermore, no official map exists clearly indicating the areas most affected by radon.
The fact is that radon gas levels can fluctuate widely, even between two neighbouring houses. That said, some particularly high concentrations have been observed in various sectors, including the regional county municipality of Antoine-Labelle, the municipalities of Oka, Mont-Saint-Hilaire and Saint-André-d’Argenteuil, as well as the Mont-Laurier and Sherbrooke regions.
Carrying out a test will put your mind at ease!
How Can I Test my Home?
Radon testing monitors are simple to use, inexpensive, and available in hardware stores or online. To conduct a test, place the device in the home’s lower-storey rooms (ideally in winter) to measure concentration levels.
A single-use monitor costs less than $50. More sophisticated models, smart and reusable, cost around $250.
If a test (done properly according to standards) shows acceptable radon levels, you don’t have to repeat the test regularly. In fact, you only need to retest after major renovations, or if the house’s layout has changed since this can affect how the radon gas circulates.
In short, a minimal investment can reassure both homeowners and potential buyers.
What Should I Do If the Results Are Positive?
If the levels found exceed 200 Bq/m³, several solutions are possible:
- Seal cracks, gaskets, and service connections touching the ground to block radon’s main entry points.
- Improve mechanical ventilation with a heat recovery ventilator (HRV) or an energy recovery ventilator (ERV), for example.
- Reduce pressure beneath the slab and around the foundation by installing a depressurization system that vents the radon gas outside.
These corrective measures are fairly affordable!
A Radon Check: An Asset That Boosts Buyer Confidence
In real estate, assurance is a compelling sale’s argument. Being able to say that a house has been tested for radon, and that the results conform to guidelines, can make a difference. The buyer can accordingly feel confident about purchasing the property.
Nevertheless, to avoid needlessly raising fears, it will be important to specify that your property is no more at risk of high radon than any other, and that you only tested it for your own peace of mind.
Indeed, in the Declaration by the Seller, the homeowner must disclose high radon levels as well as if the issue has been addressed. It’s always best to be honest with buyers to prevent problems in the future!
Conclusion: Radon, a Manageable Risk
The presence of radon in Québec homes is by no means inevitable. It’s a real risk, but a manageable one thanks to simple tests and effective corrective measures.
In other words, don’t let an invisible gas cast a shadow over your real estate investment. Have your property tested, fix the problem if needed, and enjoy your home to the full.