Efficient ventilation isn’t a luxury — it’s essential for dealing with the unique challenges of Québec’s weather
At AirGreen, we know that every mechanical ventilation system must be designed specifically for Québec’s climatic realities: harsh winters, summer humidity, extreme temperature swings, and increasingly airtight buildings. A basic off-the-shelf installation simply doesn’t cut it. That’s why we conduct dozens of evaluations each year across Greater Montréal, including Laval, Longueuil, the North Shore, and the South Shore, to adjust or replace ventilation systems that are poorly configured or unsuited for local conditions.
In this article, we explain how to recognize the signs of a poorly adapted ventilation system, what the risks are both short- and long-term, and how we intervene in real-world cases to optimize or replace outdated or improperly set up systems.
Extreme climate = specific ventilation needs
Québec is defined by an intense seasonal climate:
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Long, cold winters: temperatures dropping below -25°C
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Hot, humid summers: often over 30°C with high humidity
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Transitional seasons marked by major swings in humidity and pressure
In this context, proper ventilation must:
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Provide a steady supply of fresh air, even in winter, without overcooling the home
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Remove moisture quickly to prevent mold
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Filter out pollutants while recovering heat
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Automatically adjust to outdoor conditions
Case study: an overpowered system in a duplex in Ahuntsic
We were recently called to a renovated duplex in Ahuntsic. The owners complained of a constant cold draft in winter and a dry, irritating indoor environment. The setup included an oversized commercial HRV, configured to run at maximum speed year-round, with no seasonal adjustment.
Problems identified:
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Air too dry: indoor humidity dropped to 25% in January
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Loud, energy-hungry HRV
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Overventilated rooms with thermal discomfort
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Inappropriate filters (MERV 8 instead of MERV 13)
AirGreen’s solution:
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Replaced unit with a Venmar N Series 250 CFM HRV
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Integrated CO₂ and humidity sensors
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Automatic adjustment based on real needs
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Integrated HVAC installation with wall-mounted remote
Result: Comfort restored, lower electricity bills, and better air quality within 10 days.
Signs your ventilation system isn’t suited to Québec’s climate
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Frost forming in air ducts or around the unit in winter
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Extremely dry air in January-February despite using a humidifier
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Window condensation even with regular airing
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Overheating or odors in ventilated areas during summer
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A loud system that runs continuously without pause
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Dust buildup despite using filters
Common HVAC installation mistakes in Québec homes
1. Imported systems not built for Québec winters
Some HRV/ERV models designed for milder climates can’t handle thermal shock.
2. Poor insulation or no heat recovery
Cold air is pulled in directly without preheating, leading to major energy loss.
3. Unbalanced airflow
A poorly calibrated system may extract more air than it supplies, causing negative pressure inside the home.
4. No HVAC maintenance
Clogged filters, faulty sensors, and blocked ducts all reduce overall system performance.
How AirGreen customizes your ventilation for Québec weather
Every building is different. We provide:
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Comprehensive HVAC diagnostics, including airflow, temperature, humidity, and CO₂ testing
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HRV/ERV upgrades or replacements with models built for northern climates
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High-efficiency filtration upgrades (MERV 13+) to capture pollen, dust, and VOCs
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Smart system controls with seasonal programming
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Customized HVAC maintenance plans, including filter changes, cleanings, and system inspections
Real-world example from Brossard: a Novoclimat-certified new home with poor ventilation
A family moved into a new South Shore home certified under Novoclimat. Within weeks, they noticed:
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Lingering odors, especially in the morning
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Stuffy air, even with the HRV running
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Persistent bathroom condensation
Our inspection revealed a non-compliant installation: poorly placed ducts, unbalanced extraction, and a clogged filter.
What we did:
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Repositioned all ductwork
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Replaced the HRV with a Broan AI Series 200 CFM unit
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Adjusted airflow with professional balancing
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Follow-up visit after 3 weeks to verify performance
Where we operate: Montréal and beyond
At AirGreen, we service all of Greater Montréal with speed and precision:
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Montréal (Ahuntsic, Rosemont, Villeray, Verdun…)
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Laval (Sainte-Rose, Chomedey, Laval-des-Rapides…)
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Longueuil and the South Shore (Brossard, Saint-Hubert, Boucherville…)
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North Shore (Blainville, Terrebonne, Boisbriand, Saint-Eustache…)
We offer free consultations, complete with analysis reports and photos.
Conclusion: proper ventilation = better living in Québec
A ventilation system adapted to Québec’s extreme climate isn’t optional — it’s essential. Too often, HVAC installations are generic or poorly designed, compromising comfort, energy efficiency, and the health of occupants.
Trust AirGreen to assess, correct, or optimize your home’s ventilation system. A single diagnostic could change everything.