Mold is a nasty fungus that can grow at a rapid pace and easily go unseen and spread over time if not removed. Here’s the bad news: Your house can be a breeding ground for mold spores, especially if it’s humid or if there have been water leaks or floods.
Even the most meticulously maintained homes can harbor hidden mold growth. While it might seem unlikely in your well-kept space, mold frequently develops in concealed areas where moisture accumulates — behind walls, under flooring, or in poorly ventilated corners. These infestations can remain undetected for months while potentially affecting indoor air quality and respiratory health.
“Anywhere there’s a potential for moisture, there’s potential for mold growth,” Laureen Burton, a chemist/toxicologist with the Environmental Protection Agency‘s Indoor Environments Division, told CNET.
We’ll help you find out where mold could be hiding in your house, as well as any signs to look out for. We’ll also explain any steps you need to take to get rid of the mold ASAP. Speaking of, don’t let mold grow inside your Keurig; here’s how to clean it.
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Signs mold could be in your house
A persistent musty odor can signal mold growth.
Here are several plain signs that mold could be growing in your home. If you notice any of these signs, make sure you address the issue as soon as possible to prevent the mold from spreading.
Musty odor: An earthy smell in your house could be an indicator that mold is present.
Stains on walls: If something is leaking — specifically water pipes inside your walls or ceiling — you’ll likely see water stains (or water damage). If that’s the case, mold could be growing inside the walls.
Seeing visible mold: Mold can appear in different colors and textures. For instance, it could be black, white and even green, and can be fuzzy or slimy.
Your allergies are acting up: Mold can cause allergic reactions when you inhale the spores, according to the Asthma and Allergy Foundation of America. Symptoms can include congestion, coughing, runny nose and sneezing.
7 common places mold grows in the home
Mold can be found almost anywhere, and can grow on anything as long as there’s moisture. Here are some common areas where mold can be found inside homes, according to EPA’s Burton.
- Air conditioning units: If there’s moisture buildup in your air conditioning units, it can create the perfect environment for mold growth.
- Attics: Without proper ventilation in your attic, moisture can build up, which can cause mold growth.
- Basements: Sometimes basements can be dark, damp and poorly ventilated — especially if there are no windows. And oftentimes if there’s a house flood, it’s in the basement. This makes them a prime location for mold growth.
- Bathrooms: Check around your showers, tubs, sinks and toilets for mold. Moisture builds up in bathrooms regularly, which provides an ideal breeding ground for mold.
- Behind walls: If a pipe bursts or even leaks, mold can grow without you knowing. Make sure you fix leaks immediately and clean up the spill.
- Kitchens: Mold can grow in places in kitchens where there’s plumbing, including under the sink if there’s a leak, as well as around refrigerators and dishwashers.
- Laundry rooms: Washing machines can be a breeding ground for mold to grow (here’s how to kill mold in your washer), as well as sinks in your laundry room.
Clean your washer regularly to prevent mold growth.
How to get rid of mold in your house
Undetected leaks lead to widespread damage and problems like mold that are very expensive to address.
Your first step when it comes to getting rid of mold is to identify what’s causing the moisture problem — for instance, a leak or a humid home — and repair it as soon as possible. Mold can destroy your property, Burton said, so you want to act fast.
If the moisture issue is humidity-based, use a dehumidifier but make sure it’s maintained properly. Dehumidifiers can also grow mold if they’re not emptied and cleaned regularly.
Before you start cleaning, make sure you’re wearing personal protective equipment, like gloves and an N95 face mask. You definitely don’t want to touch or breathe in the mold.
If you find mold on a hard surface, clean it off with soap and water (you can also use a vinegar and water solution). Do not use bleach because bleach itself can be harmful, Burton said. As soon as you’re finished cleaning the area, dry it quickly.
If you see mold on a soft surface, like carpet or drywall, and you can’t get it dry within 24 to 48 hours, you may need to replace it.
Next, make sure there’s plenty of air circulation in the area. Do this by turning on the exhaust fan, ceiling fan, box fan and opening any windows.
If there’s visible widespread mold, or larger than 10 square feet, then you may need to get a professional to help.
Are there any preventative measures to keep mold away?
Moisture control. If an area stays damp or wet, mold will grow, Burton said. Make sure your house stays dry and clean. If you have an area in your house that’s prone to floods, like a basement, you can help prevent mold growth by not laying carpet down on cement floors — doing so could build up condensation.
Inspect your home regularly to make sure there aren’t any leaks — especially in less frequented areas like a basement bathroom.
You should also keep an eye on the humidity levels in your home. Levels should be below 60% to prevent mold growth. You can use a humidity meter inside your home to keep an eye on the percentage.
For more, here’s how to speed-clean your kitchen in under 15 minutes. Also, here’s how to clean a house or apartment before moving in.
FAQs
How can I tell that I have mold if I can’t see it?
Even if the mold is growing somewhere that you aren’t able to see, a distinctly musty smell signals that something isn’t right in your home. If your allergies kick into overdrive, that could also be a sign of mold — though your allergies can have multiple triggers, so this isn’t a completely accurate sign.
Where is mold most likely to grow?
Mold is most likely to grow in places with moisture and high humidity levels. This is why mold is likely to grow in your AC, your washer or a burst pipe behind a wall.
