How To Tell If Mold Has Spread

Mold is bad enough when you find it in one contained area, like a bathroom or kitchen. However, it can quickly turn into an expensive and dangerous problem when it spreads. You’re not alone if you’ve ever wondered how to tell if mold has spread.

New fuzzy, slimy patches on your walls and under your sink are dead giveaways that mold has spread. You can also tell mold has spread if you discover visible wet spots and bubbling wallpaper on your walls. Uncomfortable allergy symptoms, such as dry skin, sneezing, and sore throat, can also indicate heavy mold exposure.

These symptoms will only get worse as mold spreads, and they’re especially dangerous if you have asthma. Follow along as we explore how to tell if mold has spread and highlight some solutions.

Eight Signs That Mold Has Spread

Determining whether mold has spread is ultimately the same as identifying the reasons why it's doing so. Mold may be scary, but it’s easier to grasp once you learn a little bit about it. Several signs can indicate that mold has spread throughout your house, such as:

1. Visible Patches

Discovering new patches of mold is the easiest way to determine whether it has spread. Keep in mind, when mold spreads, it may appear far from where you first found it. Because of that, you must thoroughly explore your home and look for slimy or fuzzy mold patches. Some mold looks fuzzy and cottony, while others look leathery or velvety. Mold hotspots typically start small and patchy, which makes them hard to detect. Common household mold is typically black or green, but it may appear brown or white. Focus your search on areas where mold is likely to grow, such as the bathroom, kitchen, and laundry room.

2. Visible Water Damage/Wet Spots

Mold loves moisture, and that’s likely why you found it in your house in the first place. If you see new wet spots and signs of water damage, there’s a chance mold has spread throughout your house. It releases spores, which can travel through the air and water in your home. It’s more likely to spread if there are existing wet spots on your walls and floors or under your cabinets.

If you already have mold, new wet spots should inspire you to act quickly. There’s a good chance that you’ll notice even the tiniest flecks of mold in that area. If the wet spots are brand-new, clean the area and dry it immediately. This can prevent mold from spreading, if it’s not too late. Cleaning the area with white vinegar can help you kill the spores if needed.

3. The Air Is Musty

Most people are familiar with the musty odor of something that has sat damp for a while. However, you probably aren’t accustomed to this smell throughout your home, which can be unnerving. That’s especially true if you’re used to the musty odor in the room where you first discovered mold. You can tell that mold has spread throughout your home if the musty odor travels.

Mold releases microbial volatile organic compounds (MVOCs), which are carbon-based gases. You can easily smell MVOCs when you open a cabinet or closet that contains mold. If the musty odor comes from your vents when the AC or furnace runs, it may indicate mold in your air ducts. Mold can easily travel through ductwork, and the spores can spread further from there. Don’t discount musty odors, as they may help you catch mold before it spreads too far.

4. Your Allergies Act Up

When your allergies act up, it’s easy to chalk it up to seasonal changes. That may be the case, but your recent allergy struggles may indicate that mold has spread throughout your house. Mold can trigger many uncomfortable symptoms, such as sneezing, itchy eyes, respiratory issues, and a sore throat. The symptoms don’t stop there, as mold exposure can also cause chronic fatigue and weaken your immune system.

You may not notice these symptoms at first, but they’ll become more obvious when mold spreads. If these symptoms improve when you leave the house, you should know that something is wrong. Unfortunately, mold won’t likely stop spreading once it’s started, unless you do something about it. As long as moisture and mold spores are present, the problem will get worse. Schedule a mold inspection right away if you feel sick at home and suspect that mold has spread. 

5. Bubbling Wallpaper And Paint

Mold can grow anywhere where moisture is trapped. That can include wallpaper and paint, which may bubble due to the trapped moisture. This can create a tricky situation where mold may have spread, but you can’t easily see it. That’s especially true if you found mold in a nearby room and scrubbed it. Unfortunately, scrubbing mold can release airborne spores, which can make it spread.

In that case, it can seep into the paint and wallpaper on your walls. The mold behind your wallpaper may seem contained, but it can still spread. A lot of wallpaper and paint are porous, which helps mold spores travel easily. Call a mold remediation specialist if you suspect mold is behind your wallpaper and paint.

6. Persistent Carpet Dampness

Unless you spill water on your carpet, you don’t expect to step on a wet spot. That’s why you should be suspicious if your carpet feels damp for no reason. This is a sign that mold is growing beneath or within your carpet, but it may not have started there. For example, mold from an adjacent room may have spread into the area and gravitated to a damp part of your carpet. Once this happens, your carpet may persistently feel damp in areas where mold is growing.

These damp spots can grow as the mold spreads, and the problem will get worse without intervention. In some cases, mold starts in carpeting and spreads throughout the house from there. This is common after water damage, floods, or persistent pet accidents. If treating the carpet with vinegar and hydrogen peroxide doesn’t work, you must call a professional.

7. You Find New Leaks

Finding new leaks in your home doesn’t always mean mold has spread, but there’s a good chance it has. That’s especially true if you think you eliminated mold and then discover new leaks. If mold keeps coming back due to new leaks, it’s most likely going to spread throughout your home. Leaky pipes and plumbing fixtures can easily cause mold due to the consistent moisture.

Pipes are often located behind walls and under cabinets, which are dark environments. Mold can easily grow in such places, even if you’ve never had mold before. Things get much worse if you’re already dealing with mold in another part of the house. In that case, these leaks can worsen existing mold and contribute to a widespread outbreak. Patch the leaks right away to prevent mold from spreading further. 

8. Indoor Humidity Exceeds 50 Percent

Has your mold problem coincided with excessive indoor humidity? IHigh indoor humidity can cause mold issues in almost any home. Moisture is critical to mold’s life cycle, and it’s the first building block. If your indoor humidity level exceeds 50%, there’s a good chance mold has spread throughout the house.

The existing mold will release spores, which will gravitate to the more humid parts of your house. A healthy indoor humidity level is 30% to 50%, which you can control with a dehumidifier. If the level exceeds 60%, then mold is almost a sure thing, and you must act fast. The extra moisture can worsen existing mold and cause mold to grow in previously mold-free areas.

Summing It Up

You know mold has spread if you discover musty odors and wet spots in other parts of your home. Pay attention to wallpaper, paint, and carpeting for signs that mold is trapped. If you feel sick at home, but your symptoms subside after leaving, there’s a good chance you have a widespread mold problem.

Related Guides:

• Eleven Signs Of Mold In The House
• Why Is There Mold In My Toilet Tank?