Everything You Need to Know About Achieving the Ideal Humidity Level in Your Home

The right conditions can help you avoid indoor mold and mildew growth, skin and allergy flare-ups, and poor air quality overall.

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As the seasons change, so do the conditions in your home. In the hot, rainy months of the year, interior humidity rises; while adjusting the temperature to a lower setting on your thermostat can make your space feel cooler, it actually won't remove the excess moisture. For that reason, humidity becomes trapped, causing a sticky feel in the air. Unfortunately, this can breed mold and mildew growth and lead to uncomfortable skin and allergy symptoms. Ahead, discover the ideal humidity level for the inside of your house and several expert-recommended ways to adjust your home's moisture levels.

There is an ideal range.

The humidity level in your home should stay between 30 percent to 50 percent, says Richard Ciresi, the franchise owner with Aire Serv, a Neighborly company. "If your home or any part of it has a humidity reading of over 50 percent, consider installing or running a dehumidifier," he says. "An HVAC technician can take a reading or multiple readings throughout your property to determine what level of humidity is currently present."

These are the signs of too-high humidity levels.

Dehumidifiers, such as the Haier 20 Pint Dehumidifier ($159.99, target.com), can typically read the humidity in a room—but if yours can't (or you are concerned about the machine's accuracy), you can buy a separate hygrometer, notes Ciresi. Otherwise, you can often determine whether the humidity is too high by the following resulting symptoms: mold and mildew growth on your walls, ceilings, and other surfaces; a musty smell; condensation on your windows; warping or rotting floors and furniture; water stains on ceilings and walls; insects; stuffy or clammy-feeling rooms; and increases in allergies.

View of living room with houseplants
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Too-low and too-high moisture ranges can impact your health and sleep patterns.

Too little moisture in the air can have deleterious health effects. "Dry air can cause several things, like dry sinuses, dry skin, bloody noses, cracked lips, dry hair, sore throat, aggravated allergies, and so much more," Cindy Kang, the co-founder of Hey Dewy, explains. "According to the American Academy of Dermatology, dry air can make fine lines and wrinkles more noticeable, and dermatologists recommend using a humidifier, such as the Hey Dewy Portable Humidifier ($39, revolve.com), to add moisture to the air to help soothe dry skin." Plus, air that lacks moisture can disrupt the natural immune barriers that protect you from infections.

The right humidity level is also key for sleeping throughout the night. "Generally speaking, our body needs to drop two degrees Fahrenheit to sleep comfortably and remain at that temperature through the entire sleep cycle," says Ciresi. "Relative humidity readings above 50 percent can have a dramatic effect on your body's ability to lower its temperature. Even if the actual air temperature is cool, in a high humidity condition, the body is unable to perform its evaporation cycle required for cooling." For those living in highly humid, hot environments, it's important to manage both your interior temperature and moisture levels.

Open windows strategically.

Ciresi advises keeping your windows closed at night during the spring and fall, when the air is humid (above the recommended 50 percent humidity mark)."Although it may lower the temperature inside your home to some extent, it will actually raise the humidity level, making it more difficult to achieve restful sleep," he says. "If the humidity level outside is above 45 percent it's probably best not to open your windows, no matter what the temperature may be."

The age of your heating and cooling system matters.

Your heating and cooling systems can play a key role in keeping humidity at bay. "They should be able to control the humidity in your home," Ciresi explains, noting that older iterations, however, likely aren't up to this job;newer technology allows these systems to regulate both temperature and moisture levels, using less energy to boot.

Keep an eye on your thermostat.

Just as important? Setting your thermostat appropriately. "During extreme heat and humidity situations, we recommend that you leave your thermostat set to continually maintain the desired occupied temperature," Ciresi says. "There are some minor energy costs associated with this practice, but it is well worth the expense in comfort, health, and a good night's sleep." If you choose to turn your thermostat up and down at night, it could adjust the overall temperature—but could also cause a spike in the humidity. And if you simply let the temperature rise, it could disrupt your sleep and lead to a loss in energy savings, since your system will have work harder to cool your space in the morning.

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