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Jul 1

What Causes Mold on Your Walls?

Terms: Tips

Mold is bad news. It looks unsightly, spreads easily, crops up in annoying places around the home, damages a variety of materials permanently, and the worst strains can cause serious health problems! The good news is that finding mold on your walls is the first step toward removing it. Here’s everything you need to know about dealing with mold on or in your walls.

Finding Mold on Walls

Mold can grow anywhere on a wall, but it struggles to survive in sunlight and loves moisture, so it’s more common in some places than others. You are most likely to spot it high near the ceiling, especially in the dark corners, or close to the floor and baseboards where it can more easily hide. Because mold relies on moisture, it’s more likely to show up in bathrooms and similar locations that have a lot of water or water vapor.

So, what does black mold look like on drywall? While molds generally have a dark appearance, the true “black mold” Stachybotrys chartarum is especially dark, grows near sources of constant moisture, and is particularly bad news: This is the mold that can cause long-term or permanent respiratory issues, headaches, fatigue, and more.

If you see mold on your walls, there’s a good chance it could be behind your walls too, and it’s important to find out just how far the infestation has grown.

Causes of Mold on Walls

  • Leaks: A small leak in a roof or from a pipe can easily lead to mold problems. Ceiling leaks are one reason mold shows up on the top of your walls, and a slow leak from pipes is exactly what mold wants to live inside your walls. Leaks are one of the worst culprits because the constant moisture makes it easier for large-scale black mold problems to develop.
  • Condensation: Condensation occurs when water vapor in the air forms droplets on a surface. This happens all the time in bathrooms, which is one reason it’s important to leave bathroom fans on until they clear the air after a shower.
  • High humidity: This is the bane of certain climates with a naturally high level of water vapor in the air. It can collect in small spaces (think ductwork and, yes, the inside of your walls) and form condensation that allows mold to spread. A dehumidifier in the house can help deal with this.

Can Mold Behind Walls Make You Sick?

It can. Mold spreads through spores that can enter your home even if the mold is located behind walls. Even standard varieties of mold can cause issues, like allergic reactions and respiratory irritation, when the spore count is high. Mold can also be dangerous to newborns and any immune-compromised individuals. Strains like black or toxic mold are especially dangerous to humans and can cause very serious conditions.

How to Check for Mold Behind Drywall

Always watch for brown stains and water damage. If water has damaged the drywall in the past, mold may have taken up residence at the same time. Smell nearby outlets for musty odors as well.

If you recently experienced a leak in your roof or pipes or flood damage, there is a chance water could have leaked down behind your walls and created mold problems. When getting repairs, ask your contractor where the leak went and make sure they check for related damage.

You can check related spaces, like ductwork and crawlspaces, with a flashlight to see if there are any mold problems. Mold can often spread inside walls from places like these.

Ultimately, the only way to be sure where mold is located is to get a look inside. Mold test kits can check for the presence of mold on a surface, but a serious mold problem inside your walls can be identified on sight.

How to Get Mold Off Wallpaper

Mold behind wallpaper can crop up in bathrooms and similar locations where moisture can combine with materials porous enough to support mold growth. It’s gross – especially since you didn’t know it was there – but mold can spread to the outside of wallpaper too, creating a more obvious sign of a problem.

When in doubt, throw it out. There’s no good reason to risk ongoing mold problems by keeping wallpaper that’s already been damaged by mold. However, for very small mold problems that have just begun, you can try scrubbing the surface with a 1:4 ratio of bleach and water, although this can also damage some wallpaper colors. You would also need to check behind the wallpaper to see if mold has spread there unseen. These issues are why it’s rarely a good idea to use wallpaper in a full bathroom.

How to Remove Mold Behind Walls

Remove the wall. Unfortunately, mold infesting inner walls and insulation can’t really be treated. The only way to deal with it is to remove all affected materials entirely and replaced them. Professionals will try to salvage what they can during the remediation process.

How to Remove Black Mold from Plaster Walls

If you can spot mold growing directly on your plaster wall, it’s probably not actually the dangerous Stachybotrys chartarum variety: That mold needs a near-constant source of water to grow, so it can’t easily live on a plaster wall. But you’ll want to remove it ASAP.

If the mold growth is still light, you can use a mold-removing cleaner like Mold Control and a brush to scrub the mold carefully away. The good news is that plaster tends to be more durable than drywall, so a surface cleaning may be enough to remove all the mold. If the plaster has suffered water damage or series mold issues, it will need to be removed.

Remember, if you have any questions concerning mold cleanup and restoration, contact MasterPro Restoration at any time day or night for our certified removal services!