To help us provide you with free impartial advice, we may earn a commission if you buy through links on our site. Learn more

Do Dehumidifiers Help with Mold?

Do dehumidifiers help with mold - featured. An industrial dehumidifier in a room with black mold on the walls

There are countless types of mold and most homes will have some lurking in a dark corner. We asked the experts can a dehumidifier help?

Mold can have health implications and can also cause damage to properties if left untreated. It is not just homes that have been flooded that are prone to mold problems.

In fact, black mold, or Stachybotrys, makes its unwanted appearance in many bathrooms across the land. However, it is just one of the many mold variants that can be lurking in our homes.

What is mold?

Molds belong to the Fungi kingdom and can be found anywhere where there is both moisture and oxygen. Outside, they play a key role in breaking down organic matter such as dead trees and fallen leaves. But in our homes, they can contribute towards respiratory health problems like asthma as they are irritants.

They can also destruct the surfaces that they grow on and these can include paper, plaster, wood, carpets, insulation and foods.

How do you eradicate mold?

Remmington Belford is a spokesperson for the US Environmental Protection Agency (EPA), which publishes guides on how to get rid of mold and moisture in homes. He says: “Mold growth usually occurs on damp or wet materials resulting from leaks or other water problems in the building. Locating and fixing the source of these water problems is the most important step to prevent mold growth.”

Belford adds, however, that sometimes condensation from high humidity in the indoor air is the source of moisture. This is when a dehumidifier can help. He explains: “In those conditions, using dehumidifiers to maintain indoor humidity within a range of 30-60% can help decrease mold growth.” This is because they remove the moisture that mold needs to thrive. However, he gives the caveat, “…wet building materials can support mold growth even at very low relative humidity in the air.”

READ NEXT: Best Air-Quality Monitors


What does a dehumidifier do?

Dehumidifiers remove moisture from the air and in doing so, lower the relative humidity in your home. Relative humidity is a measurement of how much water there is in your home compared to the amount your air would hold if it was at saturation. If your relative humidity reaches 100%, this means that the air is so full of water, it will begin to condensate on surfaces. This is also known as the “dew point”. A dehumidifier can help you get your home to the ideal range of humidity and then help maintain this level.

Some dehumidifiers work by drawing the air over a refrigeration system, which makes the air condensate – or turn to water. This water is then collected. Others use desiccants, which absorb water. Warm air is then passed through this material to release the water, which is then collected.

A multi-approach solution

Author and blogger, Becky Rapinchuk or Clean Mama advocates the use of a dehumidifier to help tackle mold but adds that this needs to be in tandem with a pretty strict cleaning routine. She explains: “It’s necessary to remove the excess moisture in the air from the room but more importantly, mold will need to be properly and safely cleaned.” She adds that common mistakes in tackling mold include improper ventilation but also not employing a professional cleaner if necessary. In order to properly tackle a mold problem, you need to remove all of the microbial growth as well as the contamination.

Do dehumidifiers help with mold. Dehumidifier and cleaning supplies including rubber gloves and spray bottles in the corner of a room with lots of black mold on the walls

Belford agrees, adding that home owners must tackle the root of the problem first – whether a leak or condensation – before they can clean properly and deploy a dehumidifier. This initial investigation should also include trying to determine the type of mold they are tackling, not least because some have a greater impact of health than others.

He adds: “Other solutions focused on the air, such as using air purifiers, are not likely to be effective and the EPA does not recommend them to address mold problems because they cannot fix the root of the cause of mold. There is no practical way to eliminate all mold spores from indoor air, and the way to control mold growth indoors is to control water problems.”

How to pick a dehumidifier?

Finding the right model for your home is all about the size of the room and how wet it is. A shower room will be more humid than most lounges, for example. Some companies offer guides based on house size rather than room size.

If you have a larger home, it might be worth considering a dehumidifier that offers continuous drainage from a pipe as opposed to draining into a tank that will need to be emptied.

You then need to consider your budget both in terms of the initial cost and the running costs.

If you are being plagued with mold, the experts suggest that you must find the root cause first, tackle the mold potentially using the services of a professional and then continue to keep on top of the problem with observation and cleaning. It is at this point that a dehumidifier will be a huge help, combatting the moisture that mold needs to grow and reproduce.

The right model in the right place will make tackling mold far less time consuming and more effective which will have a positive impact not just on your health but also your stress levels.

Read more

In Depth