Musty smell in basements- Causes, prevention and cleanup

Musty Smell In Basements Causes Prevention And Cleanup

Musty smell in basements- Causes, prevention and cleanup.
Many of our Customers that call in for mold inspections in basements often have a musty odour complaint coming from the basement.

99% of the time the musty odour is because of your basement foundation walls are wet, either because an exterior defect, a crack in the foundation or recent water damage.

Even if you can’t see it, because of the basement finishes, the fact is that, the efflorescence caused by the wetness of the foundation and the evaporation of moisture to the inside of the basement will cause that musty smell. the smell will get stronger in rainy days and subside as it foundation dries.
We can detect it and identify it with an air quality test, or tools like moisture meters and Thermal imaging that can see moisture inside the basement finished walls.

No the white fuzzy looking stuff its not Mold. How to visually identify efflorescence in concrete?
Picture bellow shows the white fluffy powdery minerals and salts release by concrete as it dries to the interior of basement causing the musty smell.

Efflorescence On Foundation

I can’t see the concrete foundation because of basement drywall finishes how do I know is wet?

Often trough a phone consultation with us we would recommend to get a dehumidifier in the basement asap.  If you have to empty the dehumidifier every day, you have a problem with your foundation even if you don’t see it. A musty odour is often the result.

By basement is finished how to know the location that is wet? You would need a thermal scan and moisture meters tools to determine and pin point the location.

Last week we had a customer that had just moved in to a house and was experiencing a musty odour in the basement and wanted to do an air quality test to determine if it was mold and if it could potentially be hazardous. While we booked a date and time we suggested for a dehumidifier to be placed in the basement. Upon arrival we asked how often he had to empty it and the response led us to believe that even know basement is finished and no water damage is visible, our experience led us to inspect the exterior walls for moisture by using a moisture meter and running thermal imaging. Bingo problem found bellow basement window. Bellow pictures show 100%wet and thermal picture actually shows part of insulation that is wet (dark blue). No air quality testing needed and we recommended the removal of all the affected materials and expose the foundation to determine the correction necessary to fix the problem.

Moisture Detection Picture Thermal Picture Of Basement

To prevent musty odours from foundation issues or to clean up we recommend:

Picture Of Efflorescence On Exterior Foundation Wall

1- Check your exterior foundation perimeter for cracks, algae, downspouts directing water towards foundation, soil eroding towards foundation. Water is not supposed to get close to foundation walls.

2- A dehumidifier will dry the foundation and smell will stop when dried.

3- Clean up efflorescence with efflorescence cleaner available at big box stores

4- Use watertite waterproof paint to prevent after problem is fixed and dried.

Give us a call for advice or help in getting rid of that musty basement smell 1-800-520-7443


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