5 Top Causes of Mold in the Bathroom—and Expert Tips to Make It Disappear

If there’s one thing you don’t want in your bathroom—it’s mold. But all that moisture makes it all too easy for mold to take hold in the bathroom, and it can potentially create an unhealthy situation for you.

Fortunately, many of the things you need to do to get rid of bathroom mold and prevent it in the first place are pretty simple. Learn what could be causing a mold problem in your home, and what you should do about it.

Is Mold in the Bathroom Harmful?

While some people can handle mold without too much trouble, the spores can cause health issues, according to the CDC. Some of the potential health problems associated with mold exposure include:

• Runny nose, coughing, or wheezing
• Asthma symptoms
• Respiratory infections
• Headaches
• Eye or skin irritation
• Allergic reactions

If left untreated, mold can also cause damage to the materials of your home—causing the wood, insulation, or drywall to weaken and decay.

What Causes Mold in the Bathroom?

“Mold will grow where there’s moisture and organic matter,” says Michael Rubino, mold and air quality expert and founder of HomeCleanse. “Any actions that allow moisture to be present for 24 to 48 hours can allow microbial growth in the bathroom. This includes high humidity as well; some species of mold can grow in humidity above 60%.”

Here are some specific situations that can make it more likely that mold will crop up in your bathroom.

Lack of ventilation

This is perhaps the most common cause of mold issues. Failing to use an exhaust fan can leave moisture in the air and on the walls and tiles, creating the perfect environment for mold to grow.

Leaks

We’re not just talking about a dripping faucet. You may have leaky pipes beneath your vanity or inside your walls, that can slowly drip moisture without you realizing it.

Bad cleaning habits

Real talk: Cleaning the bathroom isn’t a job most people are thrilled to take on. But failing to clean it regularly can create the perfect environment for mold to thrive.

“A build-up of organic matter acts as a food source, allowing microbial growth to thrive after it opportunistically develops from a moisture problem,” Rubino says. Some bad habits to watch out for:

• Not cleaning the bathroom surfaces to remove particles
• Not washing the bath mat, shower curtains, and other machine washable textiles
• Using soaps or products that leave residue behind 
• Using harsh cleaning products with chemicals that degrade surfaces like grout, allowing organic matter and moisture to get trapped within the material 

Grout and tile problems

Misaligned tiles and cracked or unsealed grout can create crevices where water and organic materials can get trapped and promote mold growth.

Leaving things wet

If you tend to leave damp towels crumpled on the floor or let the tub and tiles stay wet, you’re making a hospitable environment for mold. Rubino suggests squeegeeing the tiles, separating the shower curtain and liner after use, and hanging the towels and bath mat to allow them to dry.

How to Get Rid of Mold in the Bathroom

If you notice mold sprouting up in your bathroom, you need to be very careful about how you treat it, as some of the techniques you may have seen online—such as using bleach—can be ineffective, Rubino says.

Fix the underlying issue

Before you get to cleaning, you have to stop what’s causing the mold—whether that’s fixing leaks, installing an exhaust fan, or ensuring that everyone uses the exhaust fan when they shower.

Use a botanical cleaner and hydrogen peroxide

A botanical cleaner (Rubino recommends Benefect Decon 30) is key to removing the mold. Spray it on nonporous surfaces, let it sit for 30 seconds, then wipe with a microfiber towel to help lift up as many mold spores as possible. Repeat this process at least three times to remove the mold and mycotoxins—the toxic byproducts that mold can release. For grout or caulk, apply hydrogen peroxide, let it sit, then wipe it away.

Keep an eye out

Even with good cleaning, you may miss some mold spores, which can easily grow back. Keep an eye on the area. “If the mold returns quickly, the colony could have permeated deep within the surface, or there could be a more significant problem elsewhere in the home,” Rubino says. You can try to clean it again, or call in a pro for more help.”

Preventing Bathroom Mold

That old saying, “An ounce of prevention is worth a pound of cure,” definitely applies to dealing with bathroom mold. Fortunately, there’s a lot you can do to stop mold from ever taking hold.

Choose the right materials in your bathroom

“When possible, use moisture-resistant materials, antimicrobial materials, vapor barriers, and an exhaust fan in the proper location,” Rubino says.

Some materials Rubino suggests keeping out of the bathroom:

• Carpeting. “These are moisture and particulate trapping surfaces. There are way too many opportunities for this surface to get wet in the bathroom and stay wet, creating the perfect habitat for mold.”
• Wood flooring. “It has a tendency to absorb moisture, and that’s exactly what you should try to avoid in a bathroom.”
• Unsealed grout. “This will allow water to remain trapped inside of the tiny pockets within the material, allowing for mold to grow.”
• Wallpaper. “Wallpaper typically traps moisture on the surface of the wall.”
• Fabric curtains or any porous decor. “If it traps moisture, it’s something to avoid in the bathroom.”

Keep your bathroom as clutter free as possible

Clutter makes it harder for you to keep your bathroom clean, it and creates tiny nooks and crannies where mold can start to form, Rubino says.

Pay attention to your air quality

Air purifiers can help remove small particles of mold and other contaminants from the air. “The fewer small particles inside, the healthier the indoor air quality and the less likely microbial growth will develop,” Rubino says.

Keep an eye out for issues

It pays to be vigilant about signs of mold and situations in your bathroom that could make it easier for mold to grow.

Rubino suggests taking a peek in the toilet tank weekly to see if there’s any signs of mold. “If there’s mold in this area, it’s a good indicator that there’s mold elsewhere in the bathroom or home,” Rubino says.

Ensure that you take care of any damaged or missing grout, signs of leaks or water damage, or missing grout that could create a place where mold can thrive. “The sooner you can catch an issue, the better.”