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By April 9, 2023August 7th, 2023No Comments

Basements are magnets for mold, but they don’t have to be! By taking a few simple, preventative steps you can prevent basement mold and save yourself time and money. There are several ways to prevent mold in basements, but for this article we will focus on the top 2 ways to prevent basement mold growth including: ventilation and air conditioning.


Limited ventilation in most basements leads to humid, stagnant, smelly air, and will eventually lead to mold growth. The main objective of ventilation is air movement. The point of ventilation is not to filter or condition the air, but rather to move it around.

Improving air circulation within the basement is possible by installing ceiling or room fans. However, in a low ceiling basement, ceiling fans could be dangerous since they might be too close to your head! Using a box fan or oscillating fan to keep air moving is a safer option. Running fans on low helps circulate air to prevent it from being stagnant, but it does not help reduce humidity. Humidity higher than 60% gives mold a perfect environment in which to grow. To truly reduce humidity, you need air conditioning or a dehumidifier.


Air conditioning involves the process of modifying the temperature and humidity of the air to make it more acceptable. Heating, Ventilation, and Air Conditioning, or HVAC, systems are used to control the temperature, and to some degree the humidity, of indoor air. Running an air conditioner in the summer not only cools the air, it also dries the air.

If you have an HVAC system that services the basement, you can help to prevent basement mold just by running it. There is a common misconception that basement HVAC systems are unnecessary because the temperature inside most basements stays relatively constant throughout the year. Remember, though, that temperature is only one of the two functions of air conditioning. If a basement stays closed up, unventilated and unconditioned, the temperature might be within the desired range, but the humidity may be significantly elevated. Mold can grow and odors can develop in a basement or living space of a home simply because the HVAC system has been turned off.

If the HVAC system is not running, then the air is not being conditioned or filtered. Without filtration, the air will accumulate dust, dirt, and mold spores that will create a bigger problem. We have conducted basement and entire home mold remediations where the only cause of mold growth was stagnant, humid air due to the fact that the HVAC system had been turned off. This is an easy to avoid problem! Keep the HVAC system on year round, and change the air filters on a regular basis. If you think your system might need cleaning, check out our post 12 Facts about Duct Cleaning – How to Avoid Scams before you decide to have it cleaned.

HVAC Systems

The most effective, but most expensive, type of basement HVAC system is a centrally-located, ducted unit. This is the best system if you have a large basement and/or a basement consisting of multiple rooms with doors and walls that restrict airflow.

A cheaper, but less effective alternative, is a window mounted air conditioner/heater unit. Window units are better suited to smaller basements that do not have multiple rooms.

HVAC systems can also grow mold inside the system, and you don’t want that! The best way to keep mold out of your HVAC is to change your air filter on time and use a good quality air filter for your system. To learn more check out our posts: How to Keep Mold Out of Your HVAC system and Top 8 Reasons Why Clean Air Is More Important Than Ever.


So, how do you get the already cool, humid air in a basement dry without cooling it further? The answer in most cases is a dehumidifier. Dehumidifiers do exactly what the name implies, remove moisture from the air. The way dehumidifiers work is that they create heat in order to absorb moisture.


Why should it matter if mold grows? Mold causes serious indoor air quality problems and can make you very sick. Even healthy adults who do not have allergies or asthma can be affected by mold and poor indoor air quality. It is now known that mold causes mental health problems as well as allergy and asthma symptoms.

To learn more about mold’s effects on mental health check out our posts: Mold and Mycotoxins: Effects on the Brain and Nervous System in Adults and Effects of Mold on Children’s Health.

To learn more about how mold affects you when you have allergies and asthma check out our posts: How Your Home Can Affect Your Allergies, Asthma and Mold, Why Fall Is The Worst Season For Allergies And Asthma, and Top 8 Reasons Why Clean Air Is More Important Than Ever.


Only mold experts can tell you for sure if you have a mold problem. Call Branch Environmental. We’re experts not only at mold removal, but at determining and remediating the underlying causes. We treat each inspection as an investigation. As a company, we believe that no one should live or work in a building that makes them sick. From hidden mold sources to major contaminants, we can identify exactly what is going on in your home and rid it of environmental toxins, often for good.

Branch Environmental – Because nobody should live or work in a building that makes them sick.


Join Thousands Of Other Customers Who Have Already Eliminated Toxins From Their Homes, And Their Lives.