How a Well-Designed HVAC Ventilation System Transformed the Air Quality in a School
Excess humidity and mold in schools are not just comfort issues—they pose a real health risk to children and staff. In this primary school located in the Villeray–Saint-Michel–Parc-Extension borough of Montréal, the situation had become critical. Thanks to the expert intervention of our AirGreen team, specialists in HVAC ventilation across Greater Montréal, we managed to turn the situation around—with measurable results within just a few weeks.
An Alarming Diagnosis: Humidity, Spores, Complaints and Concern
It all started with a series of recurring complaints: headaches, chronic fatigue, persistent odors, and cases of allergic rhinitis among several students. A thorough inspection revealed a major humidity issue in the basement and in certain classrooms facing north. Black spots appeared on the walls, indicating active mold, and the indoor air consistently showed humidity levels above 70%.
The building had been equipped with an old central ventilation system without heat recovery, with uneven air distribution and no humidity control. All this was compounded by a poorly insulated basement and clogged air ducts.
The Mission Entrusted to AirGreen: Upgrading the Ventilation System
Faced with this health emergency, the school administration contacted AirGreen, known for its expertise in commercial and institutional HVAC ventilation in Montréal and on the North Shore. After a full technical assessment, we developed a two-phase intervention plan:
-
Phase 1: Air Sanitation
-
Complete cleaning and decontamination of all ventilation ducts.
-
Certified antimicrobial disinfection in areas affected by mold.
-
Temporary installation of high-capacity dehumidifiers in critical areas.
-
-
Phase 2: Full Redesign of the HVAC System
-
Dismantling of the outdated central system.
-
Installation of a new Lennox Core HCWB17 heat recovery ventilation system (HRV).
-
Integration of a network of smart humidity sensors in each zone for dynamic regulation.
-
Why the Lennox HCWB17 Was the Best Solution
Choosing the Lennox HCWB17 was no coincidence. This heat recovery ventilation system is designed for sensitive institutional environments, offering high energy efficiency and the ability to maintain relative humidity between 40% and 50%—ideal to prevent mold growth.
Key Technical Features:
-
Airflow: 1200 CFM (cubic feet per minute)
-
Heat recovery efficiency: 75%
-
Filtration: HEPA filters + built-in activated carbon filter
-
Smart controls: Compatible with connected thermostats and the school’s centralized management platform
-
Eligibility: Qualifies for partial subsidy under the LogisVert program for public buildings
On-Site Challenges and AirGreen's Tailored Solutions
One of the biggest challenges was to complete the work without disrupting classes. We coordinated with school leadership to phase the project outside school hours and over weekends. Additionally, some ducts ran through gypsum ceilings that were hard to access. Thanks to our team of technicians specialized in institutional HVAC, we were able to remove the old ducts and install new galvanized spiral ductwork with acoustic insulation, ensuring quiet and discreet operation.
Measurable Results After Installation
Just three weeks after the new system was activated, the results were visible and measurable:
-
Humidity levels stabilized between 43% and 48% in all classrooms.
-
Complete elimination of odors and window condensation.
-
Improved concentration and attendance as reported by teachers.
-
Fewer incidents of rhinitis and fatigue reported by staff.
An independent inspection by a building hygiene consultant confirmed the complete elimination of active mold spores.
A Model for Other Educational Institutions
This project in Montréal has become a reference for other schools in the South Shore and Laval. We’ve since received multiple requests for similar evaluations. The school itself recommended AirGreen to the School Service Center, which is now considering a gradual HVAC infrastructure upgrade.
Why Choose AirGreen for Your HVAC Ventilation Projects in Montréal
At AirGreen, we believe a good HVAC ventilation system isn’t just about moving air. It should protect health, promote well-being, and optimize energy efficiency. With our expertise, certified equipment, and personalized approach, we deliver concrete solutions to real problems—whether in schools, offices, or industrial buildings.
We serve the entire Greater Montréal area, including Longueuil, Laval, the North Shore, and the South Shore, with fast, professional, and thorough service.
Facing a Humidity or Ventilation Problem?
Contact AirGreen today for a free building assessment. Let’s eliminate mold together and create a healthy, sustainable environment.