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Keeping indoor humidity levels under control is important. As the National Center for Healthy Housing explains, high moisture levels in a home can lead to a number of potentially serious health issues. These include asthma, allergies, and various other respiratory illnesses that are triggered by mold, dust mites, peeling lead paint, pests, and other issues often caused by high humidity levels. If you’ve noticed water leaks or stains, rotting woods, musty odors, rusting or corrosion, and excessive condensation, understanding how to lower humidity in a house is crucial. Continue reading to learn more about what causes high indoor humidity and how to get it under control.
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Main Causes of High Indoor Humidity
Ideally, indoor humidity levels should fall between 30 and 50 percent. There are a few possible causes for higher humidity level inside a house, including:
- High outdoor humidity levels: If it is muggy and humid outside, it is more likely to also be humid inside the home.
- Interior plumbing leaks: Leaks from sinks or other water sources will introduce more moisture into the air, resulting in elevated humidity levels inside.
- Inadequate insulation: If your home’s insulation isn’t sufficient, it will let in more damp and humid air from the outside, while also allowing more cool air to escape.
- Poor ventilation: Homes that don’t have adequate ventilation and airflow are also likely to be more humid.
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1. Use a dehumidifier.
When wondering how to reduce humidity, one of the easiest and most effective solutions is to use a dehumidifier. These machines pull air from the room over a very cold coil, which causes any moisture in the air to condense and then drop into a collection bin. As this process continues with more and more air from the room passing over the coils, the overall humidity level decreases. Standalone dehumidifiers —such as the Vremi 22-pint Dehumidifier, the top pick in our guide to the best dehumidifiers—are relatively compact solutions for a single room. But whole house dehumidifiers that connect with a home’s HVAC system are also available to decrease moisture levels throughout the entire house.
2. Turn up the air conditioner.
You may already know that heating a home can decrease relative humidity levels. However, on a hot summer day, the home’s air conditioner can help with humidity control. An air conditioner pulls air in the home over an evaporator coil containing refrigerant. During this process, heat is collected and moisture condenses on the coils, similar to how a dehumidifier works. Condensation then falls into a collection pan, and the cooler and dehumidified air is sent back into the room.
3. Use weatherstripping to decrease drafts.
The appearance of condensation on the inside of your windows may signify that they are letting hot and humid air inside. To lower humidity in the house and resolve this issue, try adding weatherstripping along the windows and doors to seal up any leaks and eliminate drafts. Adding a door sweep to the exterior doors will also help prevent cold air from escaping and humid air from getting in.
4. Use fans.
One secret to getting the humidity level in house under control is to increase airflow and ventilation. Turn on ceiling fans and place additional fans throughout the house to help accomplish this goal. The more the air moves around the house, the more humidity will be released from it.
5. Move houseplants outside.
Houseplants can also contribute to home humidity levels. Some varieties, in fact—such as spider plants, Boston ferns, English ivy, rubber plants, and peace lilies—are specifically recommended for increasing the humidity in a dry home. Moving houseplants outside when the home is very humid can help moderate the moisture situation.
6. Avoid line-drying laundry inside.
Folks who prefer to line-dry laundry might consider doing so on an outdoor clothesline rather than inside the home. As the moisture on the clothes evaporates into the indoor air, it can contribute to high humidity in the house. Moving damp laundry outside will eliminate this problem while also helping your clothes and linens to dry more quickly.
7. Open up the windows.
Figuring out how to reduce humidity in a room naturally can be as easy as opening up the windows. Even if it is very humid outside, opening windows allows for more airflow and ventilation, directing more humid air out of the house. Opening the windows also lets in more natural sunlight, which can help to dry out moist air. However, if the house is more humid inside than the air outside, opening the windows isn’t likely to help.
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8. Keep interior doors open.
Another solution for how to lower humidity is to keep the interior doors open. As with leaving windows open, this will allow for better airflow throughout the house. When rooms are closed off, the air can’t move around as much, which can increase humidity levels. Folks with a very humid basement or laundry room should prop the door open so more less-humid air from the rest of the home can cycle through.
9. Place bowls of baking soda or cat litter around the house.
Baking soda absorbs moisture, so it can be very effective at moisture control in the home. Simply place bowls of it around the house to draw water from the air and lower humidity levels. Tip: Cover the bowls with very thin cloth to help minimize spills and keep pets out of the powder. Similarly, cat litter also absorbs moisture, so locating small bowls of it strategically around the house can also do the trick to help lower humidity.
10. Place charcoal briquettes around the house.
Higher indoor humidity levels combined with stale or musty odors may both be banished by using charcoal briquettes. Yes, the same briquettes employed for grilling food—as long as they are natural, and free of mesquite and other additives—will absorb moisture and smells to improve the indoor environment. Put the briquettes in baskets or trays around the house, hang them up in old socks, or place them on shelves in any rooms that feel too humid.
11. Minimize tasks that will further increase humidity levels.
Many daily chores and practices—such as taking long, hot showers, boiling water for cooking, and using a laundry steamer—can lead to increased indoor house humidity levels. When indoor humidity levels are too high, avoid these activities or keep them to a minimum. For example, try taking a cooler shower or leaving the lid on the pot when boiling pasta water.
12. If all else fails, call in the professionals.
When struggling to answer the question “What causes high humidity in a house?” and the steps explained in this guide fail to help the situation, it may be time to contact a professional. Professional moisture control and foundation repair companies may be able to identify the source of the problem and come up with the ideal solution. Depending on their diagnosis, they may recommend a sump pump, a vapor barrier system, or sealing off leaks in the foundation.
