Radon is a natural gas that is still not talked about enough, despite the very real health risks it poses. Invisible, odorless, and impossible to detect without specialized equipment, it can accumulate in houses (especially in basements) and reach concerning levels.
In Quebec, where houses are often well-insulated to withstand the winter, conditions are favorable for its accumulation. If you are a homeowner or planning basement renovations, understanding radon is essential.
What is radon?
Radon is a naturally occurring radioactive gas produced by the decay of uranium in the soil. It can seep into homes and increase the risk of lung cancer when present in high concentrations.
Why is radon a health hazard?
When radon is inhaled, it breakdowns in the lungs and releases radioactive particles that damage lung cells. According to Health Canada, it is the second leading cause of lung cancer after smoking, and the leading cause among nonsmokers.
In Quebec, more than 1,000 deaths per year are associated with radon, and approximately 16% of lung cancers are linked to it.
The radon risk depends on 3 factors:
Radon concentration
Duration of exposure
Tobacco use
How does radon get into your house?
Radon comes from the ground and enters buildings through areas in direct contact with the ground. Foundations are usually the main point of entry.
The most common sources of water infiltration are:
- Cracks in foundation walls or slabs.
- Poorly sealed joints.
- Openings around pipes and ducts.
- Leaky sump pits.
- Crawl spaces.
- Dirt floors.
In Quebec, the pressure differences between indoors and outdoors are exacerbated by heating in the winter, which can turn some houses into veritable “radon vacuum”.
Radon in Quebec:
a largely unknown hazard
Radon in Quebec houses is more common than one might think. About 1 in 10 homes exceeds the recommended limit of 200 Bq/m³.
This is due to soil composition, the airtightness of foundations, ventilation quality, and construction characteristics.
How can you tell if your house contains radon?
The only way to know if your house contains radon is to conduct a long-term test using a radon monitor. Radon testing is simple, affordable, and safe.
To obtain a reliable result, it is recommended that you conduct the test for at least 3 months, ideally between October and April. You will need to install the detector on the lowest occupied level (often the basement) and choose a room that is occupied for at least 4 hours a day. Concentrations can vary from day to day and depending on the season. This is why a long-term measurement is essential.
Note: Two neighboring homes may have completely different levels. This is why it is essential to test your home, regardless of the results others in your neighborhood may have obtained.
How to lower radon levels in a house
In Canada, the guideline is set at 200 Bq/m³. In some cases, much higher concentrations may be found. If your home exceeds this threshold, it is recommended that you take corrective action within 12 months.
Several steps can help reduce radon levels in a home, particularly in the basement.
Here are the basic steps to take:
- Seal cracks in the foundation.
- Seal openings that come into contact with the ground.
- Cover and waterproof sump pits.
- Improve ventilation.
- Ventilate regularly, whenever possible.
The importance of consulting foundation experts
Radon control is closely linked to the condition of a building’s foundation. In our experience, we have observed that foundation cracks are major entry points for radon. Also, some renovations can alter pressure levels and increase the infiltration of this harmful gas.
If radon levels in your home are too high, the most effective solution is to install an active under-slab depressurization system, which vents radon to the outside before it enters the home.
This is where Bisson Expert’s highly experienced team can step in. Any work done on your foundation can also be an opportunity to improve radon control in your home.
If you’re planning work in the basement or if you notice signs such as cracks or water seepage, it may be wise to also assess for radon so you can take action at the right time.
Basement renovations: a strategic time to take action
Since they directly affect a building’s airtightness, airflow, and points of infiltration, foundation renovation or repair projects present an excellent opportunity to address radon.
Want to renovate your foundation to address radon in your home?
Request a quote from the experts.
In conclusion: radon, an invisible but manageable risk
Radon is present everywhere, and at high levels, its health effects can be serious. Fortunately, it is easy to measure, and targeted interventions can significantly reduce radon levels in your home.
Frequently Asked Questions (FAQ)
IS RADON PRESENT IN ALL HOUSES?
Radon is present everywhere in the ground, but its concentration varies greatly from one house to another. Only a test can determine whether the concentration has reached a dangerous level in your home.
HOW DO YOU TEST FOR RADON IN QUEBEC?
Simply use a long-term radon monitor, installed for at least 3 months—ideally during the winter—in the lowest occupied room of the house.
AT WHAT LEVEL DOES RADON BECOME DANGEROUS?
In Canada, the recommended threshold is 200 Bq/m³. Above this concentration level, corrective measures are necessary.
CAN NEW HOUSES ALSO HAVE RADON?
Yes, even a new house can contain radon. However, certain techniques can help limit its entry during construction.
HOW CAN YOU REDUCE RADON LEVELS IN A BASEMENT?
Solutions include sealing cracks, improving ventilation, and installing a subfloor depressurization system.
CAN RADON BE COMPLETELY ELIMINATED?
No, but it is possible to reduce its concentration to a safe level using appropriate solutions.