Eleven Signs Of Mold In The House

Every homeowner dreads the prospect of finding mold in their house. However, discovering your home has mold isn’t as simple as finding black and green spots on the walls. There are many subtle signs of mold in a house that you may have never considered.

Water damage, wet spots, and black or green specks on the air filter are among the biggest signs of mold in the house. You can also tell that you may have mold in the house if your indoor humidity level is above 60%. Warped floors, bubbling paint, and rusty pipes can also indicate that your home may have mold.

If you constantly have respiratory issues and allergies, it may be due to mold in the house. Follow along as we explore how to tell if your house has mold.

How To Tell if Your House Has Mold

1. Consistent Allergies

Many common household problems can cause consistent allergies and respiratory issues. For example, this is common for people who don’t replace their air filters frequently enough. However, consistent allergies and respiratory problems are also common signs of mold in the house.

You can experience many symptoms when exposed to black mold, including sneezing, coughing, and nasal congestion. This can get especially dangerous if you have existing health issues, like asthma, COPD, or emphysema. Sometimes, it’s hard to get to the root of the problem and figure out that mold is the cause. However, this is much easier if you rule out other possible causes in your house. Dust the surfaces in your home, replace the air filter, and have the air ducts cleaned to rule out these possibilities. If the issues remain, it’s worth scheduling a mold inspection.

2. Musty Odors

Your sense of smell can tell you a lot about what’s going on in your house, especially if black mold is present. Mold emits microbial volatile organic compounds (MVOCs) that smell musty and distinct. This is a natural part of mold growth, as these gases are released when mold breaks down organic material. This musty smell will be stronger when the mold in your house becomes more prominent and widespread. Many people notice a musty odor before they see any traces of mold in their homes.

At first, you may not notice the smell, especially if the mold is growing inside a cabinet or behind your walls. However, it will likely become more prominent when the mold gets out of control. That’s because mold spores spread throughout the air when the AC or furnace runs. The air will carry the spores, and also spread the smell throughout your house.

3. Strange Spots Appear

Strange white, black, or slimy green spots in your house leave little to the imagination. These concerning spots often appear in damp areas, such as beneath the kitchen sink and in the bathroom. However, determining whether the spots are mold or mildew can be tricky, as many people are unsure of the difference.

Mildew typically appears dustier than mold and lighter in color, producing white or gray spots. Conversely, mold is often black or green and has a fuzzy, slimy texture that is unpleasant to look at. Of course, you shouldn’t touch these spots to determine whether they’re mold or mildew.

Whether you have mold or mildew, you must quickly address the problem before it gets out of hand. Mold and mildew can quickly become dangerous, especially if you have existing respiratory problems. Mildew is a type of mold, and it’s much easier to get rid of than black mold.

4. Distorted Paint And Wallpaper

Have you recently noticed any distorted, warped patches in your walls? Moisture can easily warp paint and wallpaper, indicating a leak, ventilation issue, or excessive humidity. It’s easy to assume that these distortions are natural, which they can be, but they can also indicate a problem.

For example, there may be some damp air trapped in the wallpaper or beneath the paint. As mold forms, it will get worse, and the wallpaper will bubble and warp. Unfortunately, you won’t know the extent of the problem until you remove the paint or wallpaper. Then you'll know if the problem is isolated to one patch or if it’s spreading throughout the wall. In extreme cases, you may identify a gap behind the wall that’s letting outside air into your home.

5. Persistent Leaks

Leaks are among the most common causes of mold in the house because mold relies on consistent moisture, and pipe leaks provide plenty of it. That’s why it’s so important to address leaks as soon as you discover them, whether it be a faucet or a pipe beneath your sink.

In many cases, you’re more likely to hear a leak than see it, especially if you spend a lot of time out of the house. Listen closely if you hear water dripping, then follow the sound to discover the source of the leak. It’s worth keeping some plumber’s tape on hand so you can quickly address leaks as needed. You’ll likely need to call a plumber for major leaks, as the problem may be worse than you think. That’s especially true if you hear a leak behind a wall or beneath the floor.

6. Water Damage

Leaks are bad enough even when they don’t cause significant water damage. However, if you discover serious water damage, there’s a good chance that there’s mold in the house. Water damage can also eat away at wood and damage insulation and drywall.

If you recently had a pipe burst in your home, there’s likely some serious water damage. You must hire a professional to clean the damage and treat the area for mold. They will drain the water, remove the wet items and materials, and ventilate the area.

This is even more imperative after a flood, when mold can easily grow and spread throughout your house. In that case, you may need to run a dehumidifier for days or even weeks, depending on the severity of the water damage. Mold may be the last thing on your mind after a flood, but it will likely grow if you don’t act fast.

7. Spots On The Air Filter

Do you replace the air filter or furnace filter every 30 to 90 days? If so, you likely have an idea of how it should typically look when you replace it. It's important to pay attention to how your dirty air filters look so you can tell when something unexpectedly appears, like mold.

Finding dust, debris, and pet hair on a dirty filter is normal and to be expected. However, finding gray, green, or black spots with a fuzzy or slimy texture can indicate mold. Even worse, this means that mold is present in your HVAC system, which can be dangerous.

HVAC systems rely on a network of air ducts to distribute cool or warm air throughout your house. This ductwork is dark and damp enough for mold to grow. Finding mold or mildew on your dirty air filters can indicate a larger problem. Schedule an air duct cleaning if you find mold on the filter.

8. Strange Spots On Your Clothing

Most people can relate to the pain of finding stains on their favorite shirts and jackets. This is normal, but that strange spot on your clothes may have nothing to do with something you ate. That’s especially true if the spots are black, gray, or green and fuzzy or slimy.

Clothing can fall victim to mold in your washing machine, but it’s more likely to happen in the closet. This can also happen if you go on a camping trip, your clothes get wet, and you stuff them in a bag. The longer your clothes sit damp in stagnant air, the more likely mold will grow. That’s especially true if you hang damp clothes in your closet. You can prevent mold in a closet if you avoid hanging damp clothes and put enough space between your clothes.

9. Pervasive Rust

Rust may seem like a minor inconvenience, but it can also cause and accompany serious mold problems. That’s because mold and rust appear due to excessive moisture, and they go hand in hand. If your pipes are rusty and damp, there’s a good chance that mold is nearby. This is reason enough to routinely inspect your visible pipes at home. It’s better to catch and address mold and rust as early as possible.

10. Warped Floors

Do you have hardwood floors in your house? If so, you should pay attention to them, especially if you have a problem with excessive humidity. Excessive moisture can make your wooden floors warp and become uneven. If that happens, then you’ll know that the space beneath the floor is a perfect environment for mold. This isn’t ironclad proof that mold is growing beneath the floor, but there is a good chance. When you get the floor fixed, they can easily see if there is mold growing beneath it.

11. Indoor Humidity Is 60% Or More

Every homeowner should have a hygrometer, which you can use to detect the indoor humidity level. Good hygrometers cost as little as $10, and they leave little to the imagination. The humidity level in your house should sit somewhere between 30% and 50%, preferably closer to 30%. If the hygrometer reveals that your indoor humidity level is 60% or higher, there’s a good chance your home has mold. Excessive humidity is among the biggest signs of mold in a house, even if it hasn’t started growing yet. It’s only a matter of time before mold appears if the humidity stays at 60% or higher. Run a dehumidifier to fix the problem.

Summing It Up

If you experience consistent congestion, sneezing, headaches, and respiratory issues, it may indicate that there's mold in your house. Damp spots, leaks, warped floors, and bubbling paint or wallpaper are also signs of mold. If you find black or green slimy spots on your clothes, furniture, or air filter, it’s worth scheduling a mold inspection.

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