Mildew Odor

House Doctor | Gary Dymski

April 25, 2002

Q. I am going crazy trying to get rid of a mildew odor. I called a plumber, but he found no leaks. I changed the bathroom exhaust fan and have spent money on air fresheners. The odor is coming from a panel in my kitchen that provides access to the motor of the Jacuzzi bathtub in the bathroom. I've sealed all the tub tile walls, too.

My sons do spend a long time in the bathroom when they shower, about 20 minutes apiece. How can I get rid of the foul odor?

- Mitch, New Hyde Park

A. Mold and mildew are fungi that grow on the surfaces of deteriorating materials. For the growth to occur, you need a certain amount of moisture and the right temperature, between 40 and 100 degrees Fahrenheit. You probably can't do much to control the temperature, except perhaps drilling a few air holes into the wall of the access panel for better air circulation. If the panel isn't hidden, try to get a few air plugs, the kind that are used in wood siding. These plugs allow exterior walls to breathe, and they might help hide the unsightly holes.

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As for moisture, if you're sure no water is seeping in from the shower walls, perhaps water is coming in from another source. Check the faucet and drain connections and the caulk around nearby windows. You also might have a small opening in an exterior wall that is allowing moisture to seep into the area behind the access panel.

You need to find the source of moisture first, but in the meantime, try cleaning the entire area in the access panel with chlorine bleach. Start with 1/4 cup of bleach to a gallon of water. Wipe down the walls and flooring, then rinse with cool water and let dry. I'd try to use a small fan to help dry the area or at least leave the panel door off until these interior walls dry. Try cleaning a couple of times, till all of the mildew has disappeared.

Once the area is dry, place several charcoal briquets, the kind you use for barbecuing, on the floor of the panel area. The charcoal does a great job of absorbing odor.