Can Duct Cleaning Help With Mold or Mildew Smells in My House?

 Have you noticed a persistent musty smell in your home that just won’t go away, no matter how much you clean? For many Winnipeg homeowners, this odor is often traced back to the air ducts. Since your HVAC system circulates air throughout the entire house, anything trapped in the ductwork — including mold and mildew — can spread unwanted smells everywhere.

But does duct cleaning really help with this problem? Let’s break it down.

Why Do Air Ducts Smell Musty?

Air ducts are hidden behind walls and ceilings, making them easy to forget about. Over time, dust, dirt, moisture, and organic debris can accumulate inside. If the conditions are right — dark, damp, and undisturbed — mold and mildew can grow, causing that classic “old basement” or “wet laundry” smell.

Common causes of musty duct odors include:

• High humidity.

• Condensation around air conditioning coils or ductwork.

• Water leaks near the furnace or vents.

• Poor ventilation or blocked airflow.

Once mold spores are present, every time your furnace or AC runs, it pushes those odors (and potentially allergens) throughout your home.

Can Professional Duct Cleaning Remove Mold Smells?

The short answer: Yes, duct cleaning can significantly reduce or eliminate musty odors — but only if mold is actually present in the ductwork.

Here’s how it helps:

• Removes built-up dust and debris that feed mold and mildew.

• Clears out moisture-trapping dirt, making ducts less hospitable for growth.

• Sanitizes duct surfaces when antimicrobial treatments are included.

• Improves airflow, preventing stale air pockets where smells linger.

👉 However, if the odor source is outside the ductwork (like a leaking roof or damp basement), duct cleaning alone won’t solve the problem — the root cause must also be fixed.

When Should You Consider Duct Cleaning in Winnipeg?

While duct cleaning isn’t something you need every year, there are certain times when it’s especially beneficial:

• After home renovations (dust and debris settle in ducts).

• If you notice persistent musty or moldy smells.

• When airflow feels weak even after filter changes.

• If you or your family struggle with allergies or asthma indoors.

• Every 3–5 years as a general preventive measure.

Given Winnipeg’s humid summers and long heating season, scheduling duct cleaning every few years helps maintain a fresher, healthier indoor environment.

Other Ways to Prevent Mold in Air Ducts

Duct cleaning helps with existing problems, but prevention is just as important:

• Change HVAC filters regularly (every 1–3 months).

• Maintain proper humidity levels (ideally 30–50%).

• Schedule annual HVAC service to check for leaks or condensation issues.

• Seal ductwork leaks to prevent moisture intrusion.

• Run your HRV (Heat Recovery Ventilator) if you have one, to keep fresh air moving.

Final Thoughts

If you’re battling lingering mold or mildew smells at home, professional duct cleaning is often an effective solution. It not only helps eliminate odors but also improves your home’s air quality and ensures your HVAC system works efficiently.

👉 Next Up: To prevent these issues before they start, many homeowners ask about annual tune-ups. Our next blog covers exactly that — Why Is Annual Furnace & HVAC Service Important for Winnipeg Homes?