How to Check Your Home for Mold

Check for mold by visually inspecting common problem areas like bathrooms, basements, and around leaks, then use your nose to detect musty odors that indicate hidden mold growth.

1. Scan the Obvious Culprits. Begin in bathrooms, basements, attics, crawl spaces, and around windows. Look for black, green, white, or orange spots on walls, ceilings, and floors. Check behind toilets, under sinks, around tubs and showers, and anywhere water might collect. Don't forget to examine areas around HVAC vents and ductwork.
2. Trust Your Nose. Walk through each room and breathe deeply. Mold produces a distinctive musty, earthy smell that's often strongest in enclosed spaces. If you smell something off but can't see anything obvious, the mold might be growing behind walls, under flooring, or in other hidden spots.
3. Find Where Water Went. Check anywhere you've had leaks, floods, or water intrusion. Look for water stains, discoloration, or warped materials on walls and ceilings. Even if the leak was fixed months ago, mold can still be growing in the affected area if it wasn't properly dried and treated.
4. Check the Hidden Highways. Remove vent covers and look inside ducts with a flashlight. Check the drip pan under your air conditioning unit and inspect around the unit itself. Mold loves the dark, moist environment of HVAC systems and can spread throughout your home through the air circulation.
5. Hunt the Forgotten Corners. Look behind furniture that sits against exterior walls, inside closets on exterior walls, around washing machines and water heaters, and in pantries or storage areas. Don't overlook the areas around houseplants where overwatering might create moisture problems.
6. Record Your Evidence. Take photos of any suspicious spots you discover. Note the location, size, and color of potential mold growth. This documentation will be helpful if you need to call in professionals or track whether the problem is getting worse over time.