Expert Advice

How do I know if my house has mold?

Mold in the home can mean funky smells, a stuffed-up nose and, in some cases, a toxic environment. Here’s how to keep it at bay.

How do I know if my house has mold?
Pin it Brian Cairns

Sleuth and sniff When you first come into your home, see if it smells musty. Also take stock of your health: Do you have what feels like year-round allergies? If you’re continually exposed to mold, you’ll notice a consistent runny nose, watery eyes and sneezing.

Use your eyes You can search for mold on exposed surfaces, as well. It may look like furry dark growth, black stains or specks of black, white, orange, green or brown. Enlist an expert If you’re unsure whether you have mold, call in a professional inspector: Check the American Industrial Hygiene Association ( for a directory.

Keep things dry In most cases, you can prevent mold growth if you dry off wet or damp surfaces within 24 to Natural Healing 48 hours. When making home repairs, look for materials and paints that are mold-resistant. As a general rule, keep the humidity low in your home.

Get cleaned up Use a diluted solution of 1 cup of household-strength bleach per gallon of water; studies show it kills mold. Keep the area well ventilated to reduce your exposure to nasty fumes. For bigger jobs, you may need to get professionals to clean and refurbish the affected area.

Know the dangers Although most molds cause only allergy symptoms and do not pose a serious health threat, some can be more harmful. The two most dangerous types are Stachybotrys chartarum and Memnoniella echinata, both of which produce mycotoxins—byproducts of certain molds that are toxic to pets and people. Fortunately, these occur only in environments that are repeatedly wet and contain permeable materials. — John Martyny, Ph.D., associate professor of medicine and environmental health specialist at National Jewish Health Respiratory Hospital in Denver