From allergens to mold: what neglected HVAC ducts really reveal
At AirGreen, we understand that heating, ventilation, and air conditioning (HVAC) ducts play a fundamental role in indoor air quality. Throughout our many service calls across Montréal, Laval, Longueuil, the North Shore, and the South Shore, we’ve noticed that regular duct maintenance is often overlooked—at the expense of comfort, health, and system efficiency. This article takes you behind the scenes of our professional duct cleaning services, revealing what our technicians most frequently discover, the real-world consequences, and—most importantly—how to avoid them in your home.
What we often find in HVAC duct systems
1. Buildup of fine dust, hair, and textile fibers
One of the first things our technicians spot during a visit is a thick layer of dust, often mixed with hair, lint, and microfibers from clothing. These residues accumulate over time, especially in systems without high-performance filters or when filters aren't changed regularly.
Consequences:
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Lower indoor air quality.
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Higher risk for people with asthma or allergies.
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Partial duct blockages leading to reduced HVAC system efficiency.
2. Presence of mold in air ducts
Damp, dark, and poorly ventilated areas inside ducts create ideal conditions for mold growth. We often find this in homes where sealing issues or leaks have gone unaddressed.
Consequences:
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Unpleasant odors.
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Respiratory problems.
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Contamination of the entire HVAC system.
3. Insects and small animals
It’s not uncommon for our technicians to discover rodent nests, dead insects, or animal droppings inside duct systems. This tends to happen more in older homes or those lacking proper insulation.
Consequences:
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Serious health risks.
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Biological contamination of the air circulating throughout the home.
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Partial mechanical blockages in the ductwork.
Why do these issues happen?
Poorly designed or neglected ventilation
A poorly designed duct network, improperly placed vents, or inadequate insulation can lead to stagnant moisture, contaminated air infiltration, and dust buildup.
Irregular maintenance
Most homeowners don’t realize that professional duct cleaning should be done every 3 to 5 years, depending on usage, type of home, and whether pets are present.
Use of low-quality filters
Many systems are equipped with basic, low-efficiency filters that allow countless airborne particles to pass through. These filters should not only be changed regularly but ideally upgraded to high-efficiency models (HEPA or MERV 11 to 13).
How to avoid these problems in your home?
Schedule regular professional cleanings
At AirGreen, we offer full-service HVAC duct cleaning using powerful suction equipment, inspection cameras, and eco-friendly disinfectants. This service is available throughout Greater Montréal, including Laval, Longueuil, the North Shore, and the South Shore.
Upgrade your air filtration
We recommend installing HEPA filters in your central system and creating a filter replacement schedule. Our technicians can help you choose the right filter based on your system and household (pets, children, etc.).
Get your ducts inspected after renovations or water damage
During construction, debris (plaster, sawdust, dust) can enter your ducts. After any water damage or fire incident, a full cleaning is necessary to avoid cross-contamination.
Ask for a camera inspection
We provide video camera diagnostics that let you see the condition of your ducts in real time. This technology allows us to pinpoint trouble spots without any demolition.
The AirGreen advantage: expertise, transparency, and results
Through our service calls across Montréal, Laval, Longueuil, the North Shore, and the South Shore, we’ve helped hundreds of homeowners and property managers improve their indoor air quality and extend the life of their HVAC systems. Every duct cleaning we perform follows a strict protocol:
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Initial inspection of ducts and HVAC equipment.
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Protection of work areas with covers and filters.
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High-powered suction and rotary mechanical cleaning.
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Antibacterial disinfection using non-toxic solutions.
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Final inspection and detailed report.
A real example: duct cleaning in a Laval home
We were recently called by a family in Laval experiencing persistent odors in their home—even after the recent installation of a central Goodman heat pump. Upon inspection, we found their duct system clogged with plaster debris from a previous renovation. Thanks to our deep cleaning service, their system regained full performance and the air quality significantly improved. This kind of real-world case shows how essential duct cleaning is, even after installing a high-performance HVAC system.
In short: duct cleaning isn’t a luxury—it’s a necessity
Regular duct maintenance allows you to:
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Protect the health of occupants.
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Optimize the energy efficiency of your HVAC system.
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Extend the lifespan of your equipment.
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Lower heating and cooling costs.
At AirGreen, we’re committed to delivering professional, transparent service tailored to your specific needs.
Wondering if your ducts need cleaning? Contact us today for a free evaluation, available across Greater Montréal.