Find a loan that fits your project needs with HomeAdvisor's exclusive lender.Learn More
Moldy odors are created by any number of things, but usually that musty smell boils down to dampness that gets trapped in the basement by poor ventilation. Eliminate the moisture and increase the airflow and you'll probably be well on your way to curing your moldy basement problem. Of course, what constitutes curing a moldy basement may vary depending on how you intend to use your basement space. Homeowners who use their basement for storage may simply need to reduce the smell so that it no longer permeates clothes, books, and Christmas decorations. Other homeowners seeking to turn their basement into an additional living space may need to take further steps.
Moldy Basements and Basement Floors
Older homes with unfinished basements may have nothing more than dirt for a basement floor. In this case, the best solution for your moldy basement will probably be to create a vapor barrier with plastic over the dirt, lay down wire mesh and apply a thin layer of concrete over the ground to "rat-proof" the area. This combination should eradicate any odors, although you may still need to install some form of basement ventilation. In any case, you should end up with a more functional storage area.
For basements with concrete floors, the solution may be a little trickier. Some form of waterproofing may be necessary. You could have an internal plumbing problem, cracks in your foundation, or often, poor drainage can cause water to surround your foundation forcing moisture through the concrete walls. In fact, to rid a basement of moisture sometimes what's most needed is gutter repair. Leaky gutters can easily lead to the poor lawn drainage that causes mold in basements.
Mold in Basement
Of course a moldy odor in your basement usually means you have mold in the basement. Depending on the extent of your mold problem, you may need to hire a mold removal professional. Mold can eat through wood framing, basement insulation, and a number of other materials and structures. Mold spores are most potent when they become agitated and if you believe you have mold in your basement, you should probably leave the removal to a professional. Not only will a professional contractor be able to safely remove the mold, they'll be able to properly inspect the basement to ensure all the mold is removed, identify the source of your moisture problem, and recommend the best course of action to reclaim your basement space.
Turn your basement into usable space with aBasement Remodel
Moldy Odors and Basement Ventilation
Basement ventilation can be created by any number of means, the same end goal of which is to increase air circulation in your home and to allow air to escape outdoors while bringing fresh air inside the home. As much as we hear about air pollution, indoor air pollution is generally a bigger problem, today, than outdoor air pollution. The best basement ventilation systems generally use a combination of an exhaust fan and air dehumidifier/purifier. The condition of your basement and your needs will help determine which system is right for you, and discussing the situation with a basement contractor will typically land you on the answer. To completely eliminate musty and moldy odors, though, some kind of basement ventilation is mandatory.