How to Get Rid of That Musty Smell in Your Basement in 6 Steps

Basements are notorious for developing a musty smell. This is true whether you have a completely finished basement decked out with carpet and furniture, or you use this space as more of a storage or task-oriented destination. 

“The musty smell in basements is usually caused from mold, mildew, or bacteria that thrive in the humid environment created by basements,” explains Taylor Riley, a cleaning professional and co-founder of Impact Cleaning Professionals. “With that said, the best course of action is to control the humidity, remove dust, dirt, or mold spores, and ensure adequate ventilation.” 

Fortunately, there are some everyday steps you can take to get rid of that musty smell in your basement.

Start With a Thorough Cleaning 

Performing a full clean on your basement is step number one. Taking time to do this prompts you to check every nook and cranny for water accumulation, mildew, or mold. It also refreshes your space and helps it smell cleaner. 

“I always tell clients to start by doing a full cleaning, even if you want to hire a professional cleaning company to come in for a few hours to vacuum, dust, and scrub,” says Wendy Trunz, cleaning expert and head organizer at Jane's Addiction Organization. 

Deeply Sanitize Mold and Mildew 

When mold grows, it releases gasses referred to as microbial volatile organic compounds, which are responsible for the musty odor that is often associated with mold. 

“If this scent is present, it’s a pretty good indicator of a mold problem in the basement. Properly dealing with the mold growing in the basement will help eliminate that scent,” explains Michael Rubino, mold and air quality expert and founder of HomeCleanse. 

Your first step is to determine the source(s) of the mold and mildew and address each immediately while wearing the correct personal protective equipment (PPE) and following the correct protocol. This minimizes your exposure, reduces the risk of spread, and ensures you truly kill the mold. A bleach solution (equal parts bleach and water) can tackle most types of mold, as can commercial mold removers. Make sure to thoroughly clean all hard surfaces, and discard and replace porous surfaces—like carpet, drywall, ceiling tiles, and insulation—that have mold growth. 

“Hiring professionals to complete the work and ensure it’s done correctly—especially in areas like the basement—is best,” Rubino says. However, “if you are set on doing it yourself, be sure to find and take some local mold remediation classes or get recommendations from experts.” 

Invest in a Dehumidifier 

Since that musty basement smell occurs from excess moisture in the air, getting a dehumidifier can help a ton. “The quickest and easiest way to control the humidity is with a dehumidifier,” Riley says. “The size of the dehumidifier will depend on the size of the room. Keep in mind you'll need to ensure the dehumidifier is placed centrally in the basement to ensure adequate coverage of the area.” 

He adds that if you don’t have a floor drain, you’ll need to regularly empty the humidifier’s water container. Depending on the environment and the unit, this may be a daily task. 

Ensure Adequate Ventilation 

It’s not just moisture in the air that causes musty smells—it’s moisture coupled with stagnant air. Riley says that adequate ventilation can play a big role in eliminating musty basement odors. 

“Proper ventilation helps to reduce humidity and allows fresh air to circulate, dissipating stale and musty odors,” he explains. This might look like installing egress or upper awning windows, adding an exhaust fan to pull moisture up and out of the space, and/or running everyday ceiling and floor fans. 

Wash or Discard Musty-Smelling Items 

Musty odors have a way of permeating fabrics, including carpet, drapes, pillows, blankets, furniture, and clothing. Once you’ve found the source of your musty odor and have begun eliminating the issue with airflow and dehumidifying, take care to thoroughly clean all fabrics, Trunz says. In more serious cases, you may need to discard these items altogether to ensure a fresh start. 

Check Your Washer and Dryer 

If you keep your washer and dryer in the basement like many others, it’s worth checking these appliances to see if they’re the potential culprit. (If you notice your clothes also smell musty, your units could very well be the source of your issue.) “Make sure to open them to allow time to dry out and not cause mold and mildew to build,” Trunz says. You can also deep clean each of these appliances once every month or two.