Do dehumidifiers help with mold?

Do dehumidifiers help with mold? It’s true – dehumidifiers can solve a wide variety of problems in an indoor environment, but do they have the power to fight mold and prevent that pesky fungus from growing and infiltrating your space?

According to research, the best dehumidifiers can help control high humidity levels that promote mold growth. While they cannot completely banish mold spores from your home or kill mold, they can prevent the creation of an environment in which it can grow. But how will you know if a dehumidifier is helping with your mold problem? And how do they work?

We spoke to experts from the U.S. Environmental Protection Agency (opens in a new tab) and the Centers for Disease Control and Prevention (opens in a new tab) for current guidelines on dehumidifiers and whether or not they can help solve mold problems. To find out all this and more, keep scrolling, because we’ve unchecked everything there is to know about dehumidifiers.

Do dehumidifiers help with mold?

Mold is a common problem, the CDC (opens in a new tab) said. In fact, it’s thought to be a problem that affects around 70% of homes. If humidity levels are too high, mold will grow in damp, damp, and wet places, such as a bathroom or kitchen.

So, can dehumidifiers help solve this mold problem? According to a CDC spokesperson, yes and no.

“It is impossible to eliminate all mold and mold spores in the indoor environment,” they told Live Science. “However, mold growth can be limited by controlling indoor humidity. Residents might consider using a dehumidifier in homes with high humidity. A dehumidifier helps remove moisture from the Dehumidifiers should be placed in the room or rooms with the highest humidity.The target range for indoor humidity is 30%-50%.

small dehumidifier on a wooden floor

(Image credit: Getty Images)

And science highlights this point. In a study published in the Journal of Fungi (opens in a new tab)which examined the differences between adapting your temperature levels in your home and your humidity levels, found that controlling humidity is “more crucial” than maintaining a cold environment when it’s is to prevent mold growth.

However, as an EPA spokesperson points out, “If you already have mold, a dehumidifier won’t stop it.” This is because mold and mildew will grow within 24-48 hours of exposure to water, and it will continue to grow until steps are taken to remove the source of moisture and effectively address the mold problem, the Federal Emergency Management Agency. (opens in a new tab) said.

Therefore, as the EPA spokesperson explains, “If mold growth is already visible, you need to find and fix the water problem that caused the mold and clean up the mold.”

How do dehumidifiers help with mold?

As we have seen, dehumidifiers work by removing water moisture from the air. This helps improve indoor air quality, which reduces the likelihood that mold, bacteria, and fungi can take hold, as they prefer moist environments for their growth.

But how do dehumidifiers work? According to a 2021 review published in Advanced Science (opens in a new tab)Conventional cooling-based dehumidification systems dehumidify the air by:

  • Cool below dew point temperature to remove moisture by condensation.
  • A dehumidifier knows when to do this because the machines are equipped with a dehumidistat, which detects the level of humidity in the air.
  • Once it detects high humidity levels, the machine sucks in the moist air using a vacuum and this air is then passed over the machine’s refrigerated coils.
  • As it moves through the cold coils, the warm air loses the amount of moisture it can no longer hold, turning it into water. This causes the process of condensation and this water is collected in the dehumidifier’s storage bin or tank.
  • The dehumidifier then returns the air to the room via a heated coil.

This process helps change the humidity level of a room to 30% to 50% relative humidity and when this happens, mold, dust mites and other allergens are less likely to survive.

man spraying mold in his house

(Image credit: Getty Images)

How will you know if a dehumidifier is helping with mold?

You will know if a dehumidifier helps fight mold in several ways.

  • Reduced condensation on windows.
  • Reduced condensation on other cold surfaces.
  • By investing in a hygrometer, which is a device that measures the humidity levels in your home, to see if the relative humidity levels return to between the recommended relative humidity levels of 30-50%.
  • A musty smell from mold is gone/will.

If you find that your mold problem isn’t improving, even though you’ve eliminated the source of the damp and wet conditions, removed the mold, and used a dehumidifier, you may be using the wrong size dehumidifier.

Like most household appliances, dehumidifiers come in a range of sizes. From heavy, industrial-grade units to small, barely detectable models that you can sit in the damp corners of your home, finding the right size model is key to making a difference in your space.

To help you do just that, check out our guide on what size dehumidifier I need to make sure you’re using the right one for your home.