If your basement has a musty or moldy smell you’ll want to take care of it as quickly as possible. Mold can be toxic and cause health problems. Another big problem that comes with high humidity are pests like termites. All sorts of unwanted insects search for and thrive in a humid environment.
To get started, the first thing you’ll want to do is detect where the moisture is coming from that is causing the problem. This could be as simple as high humidity or something worse like foundation seepage, leaking window wells or a plumbing leak. Most of the time the problem is obvious like damp floors after a heavy rain or water around a washing machine, water heater or bathroom sink.
Most of the time this problem is caused by foundation cracks, faulty gutters or insufficient grading. Obviously, if seepage is the problem you’ll want to fix the problem as soon as possible. To prevent a musty smell or mold problem you’ll want to dry-vac and ventilate the damp area as quickly as possible. Most molds will start growing within 24 to 48 hours so get out the fans and open the windows pronto! In some cases carpeting may need to be removed to rid the musty odor.
The same advice goes for plumbing leaks and leaking window wells. If mold has already started growing and is visible it should be removed after any leaks are fixed. Small mold problems can be cleaned with a brush and some bleach water or white vinegar. Thoroughly clean the affected area, rinse the work area with a sponge and clean water and then dry completely with fans. When cleaning mold it is always wise to wear a respiratory protection mask and make sure the work area is open or ventilated (leave doors open and run ventilation fans if possible).
High Humidity Problems
A sure sign of high humidity is condensation on basement windows. The optimum Relative Humidity (RH) level for a home is 30% to 50%. Humidity levels higher than this can promote bacterial growth. To reduce humidity in your home consider drying clothes outside that you don’t put in the dryer and run the ventilation fans when showering and cooking on the stove (your range hood should blow the air outside or this won’t help).
Other than this, you should consider opening up the windows on nice days to release indoor humidity. Another option is a dehumidifier but you should be careful NOT to overuse it. You don’t want to dry out the air too much and draw more moisture to the basement which can activate dormant mold spores.
A good idea would be to get an indoor humidity meter and monitor levels closely. Does humidity increase after doing certain activities? You may be able to pinpoint problems that otherwise may not be noticeable.
Once you have stopped the moisture problem, removed any visible mold, thoroughly ventilated the area and have humidity levels under control the musty smell should be gone. If it persists, then you most likely have a hidden mold growth problem you’ll need to locate.