How To Test Your Home For Mold (And How To Get Rid Of It)

Daniel Mitchell in How To

9/27/25

This article may contain affiliate links, learn more.

Mold can creep into your home without much warning. It often hides in places you don’t check every day, and spreads before you even realize there’s a problem. Whether you’re dealing with a musty smell, visible spots, or unexplained allergies, knowing how to test for mold and deal with it is essential for any homeowner or renter. Here’s a practical, straightforward guide to help you figure out if mold is in your home and what to do if you find some.

1. Know the Signs

Mold doesn’t always show up as big, black spots. Sometimes, it’s a faint smell, like damp socks. You might see discolored patches on walls, ceilings, or fabrics. If anyone in your home is sneezing more, has watery eyes, or feels better when they leave the house, it could be due to mold in corners of the home. Watch for bubbling paint, warped walls, or persistent, seemingly unending moisture in one area. These are the signs that something’s growing where it shouldn’t.

Black mold in the corner of a wall near the baseboards and an electrical outlet.

2. Start With a Visual Check

Look in the most common mold spots first like under sinks, around windows, behind toilets, inside closets, and in basements or attics. Mold loves dark, damp areas with poor airflow. If you see something fuzzy, green, black, or even white and powdery, it could be mold. Don’t rely on sight alone, though. Some mold hides inside walls or behind wallpaper. If your gut says something’s off, trust it and dig a little deeper.

A woman looking at a corner of her kitchen that's covered in mold, a hand in her hair.

3. Use a Mold Test Kit

Home mold test kits can be found at most hardware stores. They’re usually inexpensive and simple to use. Most involve placing a dish in a room to collect spores from the air over a few days. If mold grows in the dish, you likely have an issue on your hands. Some kits also allow you to send samples to a lab for more detail. These aren’t perfect, but they can give you a clearer picture of what you’re dealing with.

A photo of some black mold on a white wall, near the baseboards.

4. Call in a Professional

If your test kit shows mold, or your symptoms persist, it may be time to call an inspector. A professional can use moisture meters and infrared cameras to detect hidden mold you’d never find on your own. They’ll also tell you what kind of mold it is and how serious the problem might be. This is especially important if you’re buying a house, dealing with health issues, or planning major repairs.

A person in a proective suit in a room where the walls are covered with large patches of mold.

5. Stop the Moisture First

Mold can’t grow without moisture. Before you remove mold, fix the source of the problem. That might mean sealing a window, repairing a roof leak, replacing a broken pipe, or improving ventilation in a given room. Dry out any wet areas with fans or a dehumidifier. Cleaning mold without addressing moisture just sets you up to do it all again later. This step is simply non-negotiable, it’s what keeps the mold from coming back.

A section of wall in a basement that's being renovated that's growing mold.

6. Clean the Mold Safely

For small spots of mold (less than 10 square feet), you can usually handle it yourself. Wear gloves, goggles, and a mask. Use soap and water or a mixture of one part bleach to ten parts water. Scrub hard surfaces and throw away anything too damaged to clean like carpets, ceiling tiles, or drywall. Never mix bleach with ammonia or other cleaners. Keep windows open and fans running while you work.

A cleaner in a protective suit crouched on the ground, cleaning mold off a wall.

7. Prevent It From Returning

Once you’ve cleaned up the mold, take steps to keep it away. Use a dehumidifier in damp areas like basements. Run exhaust fans in the bathroom and kitchen every time you cook or shower. Don’t let wet towels, laundry, or rugs sit around too long. Check your roof and plumbing for leaks at least twice a year. Mold prevention is mostly about staying dry and keeping airflow moving in the right places.

A low-angle shot of an oscillating fan in front of a window.

Mold is more than a household nuisance, it can affect your health and damage your home if left unchecked. The good news is that with a careful eye and a few simple tools, you can catch it early and handle it properly. Start by staying alert to the signs, and don’t be afraid to ask for help if you’re unsure. With the right steps, you can keep your home safe, clean, and mold-free.