Do Humidifiers Cause Mold?

Finding the ideal indoor humidity is a challenge for many homeowners. Humidity affects everything from your skin and respiratory health to your physical comfort at home. Many people rely on a humidifier to maintain healthy indoor humidity, but can they cause mold?

Humidifiers don’t typically cause mold, but they can when moldy conditions are already present. For example, if you run a humidifier when your home already has 50% humidity, mold can develop. It’s also risky to run a humidifier in a poorly ventilated room, as mist will settle on surfaces and contribute to mold.

Mold can cause many serious health problems, so it’s not worth running a humidifier unless it’s absolutely necessary. However, many people run these devices for 12 or more hours a day without a problem. Follow along as we explore how to use a humidifier without causing mold.

Can A Humidifier Cause Mold?

A humidifier can cause mold, but in most cases, it’s unlikely. That said, it can contribute to the growth of mold in your home, especially when other factors are present, such as an indoor humidity level that exceeds 60%, so you must be careful with the device'’s settings.

For example, there’s no reason to run a humidifier if your home’s indoor humidity is 50% or higher. In that case, doing so will likely raise the moisture levels too high, creating the perfect conditions for mold. You should only use a humidifier if your home’s humidity is roughly between 30% and 50%.

Is It Healthy To Sleep With A Humidifier?

It’s okay to sleep with a humidifier on at night, but placement is important. Don't run it on your bedside table and leave it on all night. Otherwise, the mist will hit you, your bedside table, and your bedding. This will leave you damp and uncomfortable, and it can also get messy. The moisture can also damage wooden furniture. Ideally, put the humidifier at least 3 feet away from you and your bed. It’s also important to elevate it 3 feet off the ground, so the mist won’t fall straight to the floor, and will mix evenly into the air.

How To Use A Humidifier Without Causing Mold

Your humidifier habits will ultimately determine whether or not you contribute to mold growth at home. When in doubt, follow the instructions that came with the machine. Humidifiers can drastically change your home’s humidity, so they should be used properly. Your humidifier will not cause mold if you do a few things, such as:

Adjust The Settings

There is no scenario where you should program your humidifier to exceed 50% humidity. Doing so can contribute to mold growth and cause respiratory problems. Dust mites and other allergens thrive in excessive humidity, so you must monitor the moisture levels in your home. Invest in a hygrometer so you can quickly check the indoor humidity.

This small monitor is battery-operated and easy to use. You may even want to buy a few if you have a big house with many rooms. It’s also important to know that humidity can differe in various parts of the house. For example, the laundry room and bathroom are likely more humid than a bedroom or office. Routinely check the humidity and run your humidifier only when necessary.

Improve Ventilation

Prioritize ventilation in areas of your home that are more prone to excessive humidity. For example, you should run your bathroom fan for up to 30 minutes after showering. It also helps to open the bathroom door to let moisture escape the room. Pay attention to the humidity in the room where you’re running a humidifier, since moisture from the bathroom can travel. You may want to open some windows and temporarily turn off your humidifier. That way, you won’t continuously pump moisture into the air while you’re also trying to let it escape from another room.

Reconsider The Location

Location is everything in real estate, but it’s also quite important when running a humidifier. Where you put it plays a huge role in whether or not mold will grow. That’s because the mist it produces can settle onto surfaces and soak into fabric. The last thing you want is damp clothing, bedding, curtains, and furniture. That’s why you should never put a humidifier on a porous surface.

Ideally, you should elevate a humidifier at least 3 feet above the floor. It’s also a good idea to put it 3-5 feet away from any clothing, bedding, furniture, walls, and electronics. Eventually, the mist can warp wood, stain furniture, and soak into your clothing if you’re not careful. Create a safe space around your humidifier to prevent mold growth.

Adjust Your Habits

Some people run a humidifiers for 12 or more hours per day without any problems. This is often necessary for people dealing with seasonal allergies and dry skin at home. However, that doesn’t mean you should run your humidifier for 12 or more hours without evaluating the situation. For example, periodically check your hygrometer if you’ve been running your humidifier for a few hours.

There’s a good chance the indoor humidity has already reached a healthy level after a few hours. Granted, it’s not easy to adjust indoor humidity if you accidentally run your humidifier for too long when you’re not home. But, you can run a humidifier 24/7 if you maintain 30% to 50% indoor humidity. Turn the humidifier off and open a window for a few hours if the humidity exceeds 50%. Don’t run it again until the indoor humidity falls below the healthy range.

Are Humidifiers Safe For Cats?

Humidifiers are safe for cats and other pets, but only when you use them as intended. Never put essential oils in a humidifier if you have pets. Many common essential oils, such as tea tree and eucalyptus, are bad for cats and other animals. It’s also important to run a humidifier at the coolest setting to prevent burns. Otherwise, your cat can knock the humidifier over and get scalded by hot water.

Placement is extremely important because cats are quite curious and can easily upset a humidifier. Put it out of your pet's reach to ensure they don’t knock it over. Otherwise, they will make a mess and potentially break the device. If you’re not sure what to do, ask your veterinarian whether running a humidifier is okay for your cat.

Summing It Up

Humidifiers only cause mold when certain conditions are present in your home. For example, mold can easily grow if you run a humidifier when your home is already at 50% humidity. Keep your humidifier 3 feet above the surface and at least 3 feet away from your bed, furniture, or clothing to reduce the risk of mold. 

Related Guides:

• Can You Put Tap Water In A Humidifier?
• Whole House Versus Portable Humidifier