Hidden Radon in Montréal: Why Your Ventilation Should Be Inspected Every Year

The Invisible Threat of Radon and the Vital Role of Residential Ventilation

In Montréal, indoor air quality is often underestimated, yet it has a direct impact on our health. A silent enemy, radon, seeps into many homes without any visible trace. At AirGreen, we frequently come across cases where a simple annual ventilation inspection helped detect and reduce radon levels in indoor air, thus preventing serious consequences for the occupants.

As experts in HVAC systems in Montréal, Laval, Longueuil, the South Shore and the North Shore, we emphasize the importance of preventive maintenance, especially in residential areas at risk. Here’s why your ventilation system should never be overlooked.

What is radon, and why is it so dangerous?

Radon is a natural, radioactive gas—odorless and colorless—that comes from the decay of uranium in the ground. It can seep in through cracks in the foundation, floor drains, or poorly ventilated crawl spaces. Long-term exposure to radon is the second leading cause of lung cancer in Canada after smoking.

In several Montréal neighborhoods, including Ahuntsic, Rosemont, Côte-des-Neiges, and certain areas of Laval and the South Shore, we’ve detected abnormally high radon concentrations in well-built homes.

Ventilation: Your Best Defense Against Radon

An effective residential ventilation system helps remove accumulated radon from indoor air and refreshes the air with cleaner outdoor air. However, this mechanism only works properly if it is maintained regularly, properly balanced, and the airflow is adapted to the building’s layout.

At AirGreen, we conduct comprehensive annual inspections of ventilation systems, including HRV/ERV air exchangers, ductwork, registers, and filters. We ensure that the systems are running at full capacity, with no obstructions or pressure imbalances that could lead to stagnant, contaminated air.

Customer Testimonial: One Inspection That Changed Everything

Last March, we were contacted by a family in Saint-Bruno-de-Montarville, concerned about a persistent odor and a heavy feeling in the air, especially in the basement. After an indoor air quality analysis, our technicians detected radon levels exceeding 250 Bq/m³, well above the safe threshold of 200 Bq/m³.

Our team immediately carried out a detailed inspection of the existing ventilation system, which turned out to be unbalanced, with blocked vents in key rooms. After a complete cleaning, a rebalance of the HRV system, and a reconfiguration of the intake/exhaust setup, the radon level dropped below 100 Bq/m³ in less than 30 days.

Why an Annual Inspection Is Essential

1. Preventing Invisible Risks

Even a recent system can lose efficiency if the filters are dirty, ducts are poorly sealed, or airflow is not adjusted for seasonal changes. Excess humidity and stagnant stale air not only encourage radon buildup but also mold—another common enemy in Montréal.

2. Avoiding Costly Repairs

A neglected system can break down, leading to high repair costs. During an annual inspection, we detect signs of wear before they become serious issues, extending the lifespan of your HVAC equipment.

3. Optimizing Energy Performance

A well-maintained system consumes less energy, lowers your utility bills, and maintains optimal thermal comfort, even in winter. This is especially true for homes with central or wall-mounted heat pumps, which must operate in synergy with the ventilation system.

Our Technical Approach at AirGreen: Precision and Transparency

Each annual inspection includes:

• Airflow evaluation in every room

• Filter, motor, fan, and damper checks

• Indoor air quality testing (radon, CO₂, humidity levels)

• Static pressure analysis of the system

• Detailed report with technical recommendations

We use certified professional equipment to ensure accurate readings and targeted interventions. All our technicians are trained to work in residential, multi-unit, and commercial buildings.

Any help for ventilation?

Since October 1, 2026, Rénoclimat no longer subsidizes air exchangers (HRVs/ERVs), and LogisVert has no measure for ventilation. Check with the City of Montréal whether municipal assistance exists for:

• Adding a high-performance air exchanger (ENERGY STAR certified)

• Replacing faulty ductwork

• Installing a high-efficiency centralized ventilation system

At AirGreen, we help you through the grant application process, from documentation to submission, to maximize your savings.

Wide Service Coverage: Montréal, Laval, Longueuil, South Shore, North Shore

We operate in every borough of Montréal, as well as Laval, Longueuil, Brossard, Terrebonne, Repentigny, Saint-Jean-sur-Richelieu, Saint-Jérôme, and more. Our understanding of local geological characteristics (especially the presence of natural uranium in certain clay soils) allows us to provide precise, reliable recommendations.

Take Action Now for Your Family’s Health

Ignoring radon means taking an unnecessary risk. An annual ventilation inspection is a modest investment for a major gain: peace of mind and protection from serious respiratory illnesses.

At AirGreen, we never compromise on quality. Every inspection is carried out with the utmost care, respecting the highest HVAC standards. We’re proud to help families live in healthier, safer homes—year after year.

Book your annual ventilation inspection today. Protect your health, improve your comfort, and ensure your home’s long-term performance with AirGreen.