How to Get Rid of Musty Smells in a Basement for Good

How-To Guides
by How-To Guides

By Judy Schumer

Getting rid of the musty smell in your basement involves more than odor cover-up. If you spray a nice smelling air freshener, you may eliminate the problem short-term—if you don’t treat the source of the odor, it’ll come back in no time. If you’ve invested time and money turning your basement into a place you love, like a home bar or theater room, a musty smell can instantly ruin the vibe.

Figuring out the cause of the musty smell is the key to getting rid of it for good. Eliminating excess moisture, mold, or mildew in your basement will not only eliminate your odor issues but will create a healthier indoor environment for you and your family.

Read on to find out what things can cause your basement to smell musty, how to banish the cause of the odors and the odors themselves, and how to prevent the musty smell to begin with.

water dripping from pipe onto concrete floor

Photo via Jo

Why Your Basement Smells Musty

Finding out why your basement smells musty is the first step you’ll need to take to eliminate the odor for good. Here are the main culprits of a smelly basement:

Mold and Mildew

Mold and mildew thrive in dark, damp places, making basements the perfect environment for these fungi to grow. If the environment permits, mold and mildew can also grow in the ducts of forced air heating and cooling systems, which allows the spores to spread far and wide.


Leaks allow water to sit for long periods, creating a breeding ground for mold and mildew. Water can come inside via leaky pipes or from outside through cracks in window frames or the foundation itself. If you have a washing machine in your basement, leaks from hoses could be creating damp floors or walls. Rain gutters and drains that aren’t working correctly can also direct water into your basement.


Condensation forms when warm air meets cooler air. Because most, if not all, basement walls are underground, the air in a basement is significantly cooler than the air in the upper level of your house and even outside air.


When warm air from upstairs or outside enters your basement, the cooler air cannot hold the same amount of moisture that warmer air does, so the excess moisture is deposited on your walls and floors as condensation. The same thing happens when warm, humid air from outside enters your basement either from an open window or air leaks around windows or doors.


A dryer in your basement is also another source of condensation because the drying process involves pulling moisture from clothes with heat. If your dryer vent isn’t properly sealed, the moisture that should be heading outside will form as condensation on your walls.

How to Stop the Source of Musty Smells in a Basement

The ideal way to stop your basement from smelling is to nip it in the bud. Here’s how to wipe out moisture and mildew.

How to Remove Moisture in a Basement

  • Install a dehumidifier, keep it set at 40-50 percent humidity, and empty it often.
  • Add a window exhaust fan to improve air circulation, so condensation doesn’t form.
  • Insulate all pipes with insulating wrap.

How to Kill Mold and Mildew in a Basement

If you can spot mold and mildew in any areas of your basement, clean it up ASAP. Use a designated mold and mildew remover to kill any mold and mildew on your walls, carpet, windows, or doors. Be sure to toss out any rags that were used to clean the mold to keep the spores from spreading.

How to Remove Musty Smells in a Basement

After determining the cause of your basement’s musty smells and fixing the issue, an unpleasant scent still might linger. Here’s how to remove the smells that are in your basement:

  • Place bowls of vinegar or baking soda around the basement to absorb odors. The odors will disappear within a few days.
  • Place containers of activated charcoal around your basement to absorb odors.
  • Use a Damp-Rid product, which is designed to keep moisture and musty odors at bay.
  • Thoroughly clean the basement. Wash all hard surfaces with a 1:1 mixture of vinegar and hot water or a good-quality bathroom cleaner. Completely dry all cleaned areas.
  • Rent a carpet steamer to deep clean carpets, taking care not to saturate them, which can cause more mildew down the road.

How to Prevent Musty Smells in a Basement

Once you’ve gotten rid of the musty smell in your basement, there are a few things you can do to keep it from coming back:

Prevent Mold and Mildew

The best way to prevent mold and mildew is to get rid of the moisture in your basement. As we mentioned above, a dehumidifier is a fool-proof way to handle humidity issues. You can also use Damp-Rid, changing out the containers as soon as they get full.

Weatherproof Your Basement

Seal any windows and doors with weatherstripping to prevent dampness from seeping in. Have any foundation issues taken care of so water can’t leak into your basement. 

Wrap All Exposed Pipes

The condensation that forms on pipes can be prevented with proper insulation to keep the lines from getting too cold. Without the condensation, you won’t have dampness.

Install Outdoor Drainage

Directing water away from your foundation will not only keep your basement dry but can prevent severe damage to your home’s foundation. To keep water away from your foundation and the inside of your basement, consult with a drain specialist.

Keep Your Ductwork Clean

Ductwork can develop condensation, which plays host to mold and mildew spores. Have your ductwork cleaned regularly to keep mold and mildew from spreading through your home and to your basement.

black mold on corner of wall

Photo via Brenda

When to Call a Professional

In serious cases, professionals will have the tools and materials you need to fix the source of your basement’s musty smell. In these situations, it’s best to call in a professional plumber or basement specialist:

  • You’ve eliminated all sources of moisture and mold or mildew and your basement still smells
  • Broken or cracked pipes
  • Condensation issues
  • Leaky windows
  • Cracked foundation walls
  • Moldy or mildewed drywall
  • Large amounts of black mold (bigger than the size of a beach towel)
  • Outside problems that allow water to seep into your basement


Have you ever dealt with a musty-smelling basement? How did you get rid of the smell? Let us know in the comments; we love to hear from you!

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  1 question
  • Ann Ann on Aug 19, 2022

    How you you get rid of old cat pee smell in crawl space, tenants cat used it as a litter box. Thanks.

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  • I got rid of the smell by cleaning the sump pump barrel sides with chlorine bleach and water and then pored the rest of it into the bottom of the sump where there is sometime a small amount of water. That alone solved the problem

  • Jenthewren Jenthewren on Aug 19, 2022

    We have this in our bedroom, we have a flat roof & seem to think this has been caused by the workmen from the Internet / cctv etc climbing on the roof causing a leak.