Attic mold, bathtub mold, kitchen sink mold – these are what come to mind when someone asks you to name the most common places you may find mold. But did you know that nearly every HVAC system experiences mold growth at some point? Even more concerning is the fact that mold affects the indoor air quality in a home, which can lead to respiratory problems and other issues that can mean huge bills for your family.

Remove Mold from Your Home’s Air Ducts

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Why Mold Thrives in Your HVAC System and Air Ducts

A warm environment with high water content is a breeding ground for mold. When cold air passes through the duct system, water vapor can form and accumulate in air ducts. When humidity levels are high, the water remains instead of evaporating, forming the ideal atmosphere for mold growth.

Mold typically gets its intake from dirt, debris, pollen, animal dander, and dead skin cells that accumulate inside the duct along with water contamination. The inorganic and organic compounds provide mold with the nutrition it needs to grow, travel, and spread throughout the HVAC system.

An oversized HVAC unit can also cause mold to develop in air ducts by switching off before dehumidifying the air. The excess moisture that results from the process can build up in your ductwork and rooms. And if this moisture never gets an opportunity to dry out, it can result in mold growth. As such, you must invest in a proper size AC for the space you have.

Signs of Mold in Air Ducts

Here are some telltale signs of mold growth in the air ducts:

  • There is visible mold growth around the drip pans and air ducts and within the intake vents
  • You feel your eyes, throat, and nose becoming irritated when you turn on air conditioning
  • You experience ongoing allergy symptoms, like watery eyes, rashes, and a runny nose
  • You experience unusual feelings of dizziness, nausea and fatigue
  • There is a musty odor or smell that grows in intensity when you switch on air conditioning

How to Prevent Mold Growth

Because air duct mold is not always easy to spot, few homeowners search for ways to prevent its spread. Fortunately, you can avoid this problem by taking the following steps.

  1. Clean and disinfect ductwork
    To do this, you’ll have to make a chemical cleaner. The most effective (and affordable) option is the mixture of water and chlorine bleach. Add one cup of bleach for each gallon of water you use. Once the cleaner is ready, make sure you can clean all the ductwork, or you may fail to remove the spores. It’s important to kill all the spores if you want to resolve the problem of mold in your HVAC system fully. If you have insulated vents, they may need to be replaced for the spores to be completely eradicated. As an additional measure, you can use bladders to isolate each ductwork section you clean to prevent the spores from spreading to other areas of the HVAC.
  2. Fix leaks
    If you’re experiencing drainage problems, you’ll need to call in a professional to restore its proper functioning. An experienced technician will seal off the ducts and pipes to ensure that the mold doesn’t grow in the rest of the system while they’re getting the HVAC system to drain again properly. Besides leaks, fix things that have become porous (like insulation or filters that have become wet).
  3. Keep humidity under control
    One of the most effective ways to prevent mold growth is to achieve ideal humidity levels in your home. You can get a humidity meter to determine the current level. If the meter reads 55 percent or above, your home and air ducts are vulnerable to mold growth that could be toxic to breathe in. To keep the level of moisture in the air balanced, consider investing in a dehumidifier as this will help keep the moisture levels in check.
  4. Get sealed return ductwork
    Sealed return ductwork offers adequate air supply and keeps contaminants from getting into the HVAC unit from the garage, crawlspace, basement, and other high particulate areas. Try minimizing the air duct temperature loss or gain between the room registers and air handler, and vice versa. The registers include the vents on your walls, floors, air return grill, and ceilings. The system should be installed in a way that the “static air pressure drop” is within the vendor’s design specifications. Plus, the return system size should be there to generate the correct return airflow.
  5. Check air duct type
    It’s also a good idea to check what material has been used to manufacture your ductwork. The most popular materials are metal sheet, fiberglass and flex duct. Different duct materials require different cleaning methods. For example, it’s much easier to remove mold from a bare metal sheet. However, fiberglass duct liner or fiberglass ducts are challenging to clean and should be replaced instead in most cases.
  6. Get a mold growth inhibitor
    Once you’ve removed the visible mold from your HVAC, it’s time to ensure it never comes back. The most effective step is to use a mold growth inhibitor, as it can successfully prevent the regrowth of mold after removal. Look for an EPA registered mold inhibitor like Goodway’s CoilShine-BC as they’re safe to use and last for a couple of years. Without the EPA registered label, you may end up spreading the wrong chemicals in your HVAC system.

The Takeaway

The steps above are effective for preventing the growth of mold in air ducts. However, the work involved can be overwhelming for some homeowners. That’s where The Disaster Company comes in. You can schedule an appointment with us if you identify any signs of air duct mold. Our process of mold removal varies according to the severity of mold growth. You can rest assured that our Utah mold cleanup team will mitigate all affected materials, cleaning, treating, and sealing the area for maximum safety.