Condensation on HVAC air ducts is a fairly common issue and will often lead to mold beginning to grow. Condensation can form whenever there is a big difference between the temperature of any surface and the air that surrounds it. You know how water droplets can quickly form on a cold drink in hot weather?

Well, the same thing can happen inside or outside of your ductwork whenever the temperature of the air around the ducts is much higher or lower than the temperature of the air flowing through the ducts. Metal ductwork is especially prone to condensation since the air flowing through the duct causes the metal surface to quickly become hot or cold.

If you frequently have issues with condensation on your air ducts, it can result in poor indoor air quality due to mold. Condensation can also easily lead to water damage and result in water spots on your walls or ceilings. Luckily, preventing and overcoming issues with condensation on your air ducts can be fairly easy, and here are some of the most effective options for doing just that.

Insulate Metal Ductwork

The best way to overcome issues with condensation is by insulating metal ductwork. Again, condensation forms whenever there is a major difference between the temperature of the air inside the ducts and the temperature of the air surrounding them. When the ducts are insulated, it will block out the surrounding air so that it can’t come into contact with the ducts. This results in the temperature on the inside and outside of the metal duct staying around the same, which prevents condensation from forming.

When you leave your heating or air conditioning running, you usually don’t need to worry all that much about condensation on any of the ducts in the main living areas. As long as your HVAC system is working correctly, the temperature in your home should always remain fairly consistent. This means that the temperature of the air in the ducts will usually only be around 20 degrees higher or lower than the current air temperature in the home, which lessens the chances of condensation forming.

Where you really have to worry about condensation is on the ducts in the unconditioned parts of the home like the crawl space and attic that don’t receive any heating or air conditioning. Since condensation can be a big issue in these areas, it is important to make sure that the ducts in these areas are completely insulated with no gaps between the pieces of insulation. Condensation can also sometimes be an issue for basement ductwork in the winter simply because many basements are usually colder, which means you may also want to insulate your basement ducts if they frequently have issues with condensation.

Control the Humidity Level in Your Home

The more humid your home is, the greater chance there is that condensation will form on your air ducts. As such, it is always a good idea to try to control the humidity level in your home to prevent it from becoming too high. Ideally, the relative humidity level in your home will always remain constant at around 40%-50%. If the humidity level ever goes above 60%, there is a much greater risk of condensation forming.

High indoor humidity always tends to be a bigger issue in the summer months, and this is simply because warm air usually contains much more moisture than cold air. Your AC system will often be sufficient for keeping your home’s humidity level in check since air conditioning also works to remove moisture from the air as it cools it. If you do often experience issues with high indoor humidity in the summer, you may want to invest in a whole-home dehumidifier as this will remove far more moisture from the air than your AC alone. In this way, you can better manage your home’s humidity level and lessen the chances of condensation issues on your ducts.

Improve Attic Insulation and Ventilation

Attics usually have open vents so they often get fairly cold in the winter, which can easily lead to condensation forming on or inside any air ducts in the attic when your heating is running. The best way to prevent this is, again, to make sure that the air ducts in your attic are fully wrapped with insulation. Ensuring the attic itself is also properly insulated can make a major difference since this will help it to stay warmer in the winter.

Condensation on attic vents is typically a much bigger problem during the summer. An attic also absorbs a huge amount of heat through the roof in the summer, which often results in the temperature inside it rising well into the 120s or even 140s. If the attic doesn’t have sufficient ventilation, the humidity level inside it can also skyrocket during the summer. Both the extreme heat and high humidity create ideal conditions for a huge amount of condensation to form on the air ducts.

The easiest way to avoid condensation on attic vents in the summer is by making sure the attic has adequate ventilation and is well insulated. Insulation under the roof will help to block out lots of the heat, while ventilation can create a breeze that will also prevent the attic from getting as hot. Attic fans can also be a huge help as they will work to draw the heat and humidity outside.

Make Sure Your Crawl Space Is Sealed and Insulated

For homes that have a crawl space and not a basement, the air ducts that supply the ground floor of the house are almost always mounted to the floor joists in the crawl space. Condensation usually isn’t an issue for the ductwork in the crawl space during the summer when you’re using your air conditioning.

Crawl spaces tend to be fairly cool, so condensation normally won’t form on the ducts since there isn’t that much of a difference in temperature between the air flowing through the ducts and the air surrounding them. The only time you may have to worry is if your crawl space doesn’t have adequate ventilation since this can lead to it becoming much hotter and more humid.

When you do need to worry about condensation is during the winter when the temperature in your crawl space will usually be much colder than the hot air flowing through the ducts. Making sure that the ducts are fully insulated is usually sufficient for preventing condensation. That said, it is also a good idea to close or block the air vents in your crawl space during the winter to keep the cold air out.

Any cracks or holes should also be fully sealed for the same reason. You may also want to consider insulating the walls of the crawl space since this will also help keep out the cold and ensure it stays warmer during the winter. The warmer your crawl space stays during the winter, the less you’ll need to worry about condensation issues.

If you’re experiencing frequent issues with condensation on your air ducts, you can count on the team at AJ Danboise Plumbing, Heating, Cooling & Electrical for help. We can assist with insulating your ductwork and also make sure that none of your ducts are leaking since this can also increase the risk of condensation forming. Learn more about air duct cleaning!

We can also install a whole-home dehumidifier in your home to help you manage humidity issues. To learn more about the ways you can prevent condensation issues or to schedule any HVAC or indoor air quality service in the Farmington Hills area, contact AJ Danboise Plumbing, Heating, Cooling & Electrical today.

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