Why is Mold Growing in My Air Ducts?

Image for Man looking in air vent

From advanced furnace filters to whole-house air purifiers, your HVAC system gives you several options to improve your home’s indoor air quality. However, a hidden intruder may be in your ductwork contaminating your air without you even realizing it: mold. Discover what you should know about mold in your air ducts, as well as how to remove mold and prevent it, to help you breathe easier in your home.

Why Can Mold Grow in Air Ducts?

Mold can prosper in virtually any dark and damp environment, and air ducts are no exception. The air that circulates through your HVAC system often contains humidity that can condense on the interior walls of your ductwork. This provides a source of excess moisture for mold to feed off of.

To understand how mold finds its way into your air ducts in the first place, you must understand where your HVAC system draws air from. In some cases, members of your household may carry mold spores in with them from outside that circulating air then picks up. Other times, your HVAC system may draw air up from your basement, crawl spaces, and other dark areas of your home that could have some mold.

What Are the Risks of Mold in Your Ducts?

Mold creates a characteristic musty odor that no one enjoys breathing in their home. However, mold in your duct system is more than a simple nuisance — it’s a health risk that you should address as soon as possible. Black mold is particularly toxic, and the health risk it poses only worsens as more spores circulate through your ducts.

Prolonged exposure to mold spores can lead to various health symptoms. Common results of mold exposure include asthma episodes; headaches; and eye, nose, and throat irritation. In more serious cases, mold spores can cause people to experience fatigue, difficulty concentrating, nausea, vomiting, and diarrhea. These symptoms will often persist as long as the person is exposed to mold.

What Are the Signs of Mold in Air Vents or Ductwork?

While the most obvious sign of mold in your ducts is the musty smell it creates, this is not the only thing that can help you identify a mold infestation. You may see a black, dust-like coating on your air vent registers that develops as spores come into contact with the registers when air blows out of your ducts. Mold spores that cling to a vent register can even cause a new mold colony to start to develop in the wall around it.

Unfortunately, one of the easiest ways to detect mold in your ducts may be to observe the health effects it can cause in your household. If members of your family experience symptoms of mold exposure, the symptoms will usually worsen when your furnace or air conditioning system is on. Turning your HVAC system off stops circulating spores through your home, and they will settle inside your ductwork.

How Can You Prevent Mold in Your Ducts?

If mold is already present in your ductwork, the only way to be sure that it is removed completely is to hire a heating, air conditioner and indoor air quality professional for duct cleaning. This will get rid of mold colonies deep in your ducts that you couldn’t reach on your own. Because of this, preventing mold growth in your ducts is a much better plan than addressing the problem once it arises.

The key to preventing mold is reducing the amount of moisture that enters your ductwork. This involves patching any gaps in your ducts as well as small leaks in plumbing near your ductwork. Avoid closing air vents or blocking them with furniture to promote air circulation and reduce condensation in your ducts. 

Additionally, you may also want to consider a whole-house dehumidifier. This will help to keep your home’s air at a healthy humidity level.

Contact Edelman Inc. for Air Duct Cleaning Services in Champaign, IL

Mold in air ducts is a problem that can easily go unnoticed, but it isn’t one that you have to live with. Increased mold exposure can cause several health issues if left untreated. If you need professional duct cleaning or other HVAC repairs and maintenance, contact Edelman Inc. today.


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