Featured in Better Homes & Gardens: The 3 Best Evaporative Humidifiers, According to Our Tests

Read the full article of my latest feature in Better Homes and Gardens issue for April, here!

An evaporative humidifier relies on a fan that blows water from the device’s water tank through a wick or filter. Compared to ultrasonic models, evaporative humidifiers tend to cost less up front, though that balances out with the long-term upkeep cost of replacing filters.

Evaporative humidifiers have the perk of being self-regulating, but ultrasonic humidifiers have the benefit of running more quietly. Fortunately, there are some quieter evaporative humidifiers on the market, such as the Stadler Form Oskar Humidifier and the DobeTiny Humidifier.

According to Lycia Thornburg, MD, FAAD, fellow of the American Academy of Dermatology, evaporative humidifiers are beneficial because they typically self-regulate, so they won’t cause humidity levels to get too high in the room. That doesn’t mean they always have an automated shut-off that turns the device off when it runs out of water; instead, a self-regulating humidifier is one that detects humidity levels in the air and adjusts the amount of moisture it releases, releasing less over each session it’s running.

“This feature is in contrast to cool mist ultrasonic humidifiers, which can provide too much humidity into the air, potentially leading to condensation or even worse mold indoors,” Thornburg explains.

Capacity and Room Size

“Of course, size is an issue when deciding on where to place in your home,” Thornburg says. “Aesthetic considerations aside, it’s important to choose a device that has specifications for the square footage of your home.”

A humidifier’s capacity often goes hand-in-hand with the room size. The evaporative humidifiers on this list span from 0.66 gallons, ideal for a room under 250 square feet, to nearly 2 gallons, which covers a larger room up to 1,200 square feet. For an average-sized room of 250 to 400 square feet, anything near 1 gallon is typically a good fit.

Care

The best evaporative humidifiers for your home are the ones that feel easy and convenient to care for. No matter the humidifier, it’s best to use distilled water to minimize risk of bacterial growth in the water tank.

Next, consider the filters or wicks the evaporative humidifier uses. Do they require a specific brand of filters? Are the filters hard to buy in-store or online? Make sure you choose a product that won’t make restocking on filters a hassle.

From there, you’ll want to consider how easy it will be to refill and clean the water tank, as this is a chore that needs done regularly.

“Using filtered water and changing the water daily will also help prevent mold or bacteria from growing in your humidifier,” Mendez advises. “Empty and wash the collection bucket and change the filters as often as directed by the manufacturer.”

Typically, you should expect to clean the water tank about once per week. Some models offer dishwasher-safe tanks, while others are hand wash-only.

Features

Whether its LED lights, sleep modes, or essential oil diffusers, humidifiers may include any number of extra features to boost their functionality. But you may or may not benefit from a humidifier that has all the bells and whistles. Sometimes, the best evaporative humidifier is one with a simple interface that just gets the job done.

One feature that can be beneficial is a built-in hygrometer, which will gauge a room’s humidity level and make sure it doesn’t get too high. “If your home becomes too humid (above 50%), it will promote mold and dust mites,” says Kenneth Mendez, CEO and president of the Asthma & Allergy Foundation of America (AAFA).

If you find an evaporative humidifier you like but it doesn’t have a hygrometer, we recommend buying one separately to monitor the room’s humidity. “It is possible for air to become too humid if you leave the humidifier running continually without monitoring humidity, and this can encourage the growth of mold and bacteria in the room, as well as shorten the life of your humidifier,” McKeon says.

For some people, a humidifier that doubles as an essential oil diffuser can help you breathe easy in a pleasant and refreshing way. However, you may want to skip this feature if someone in your home has certain health conditions like asthma or if you have pets in the home.

“AAFA does not recommend using essential oils if you have asthma,” Mendez warns. “Breathing in the particles released by essential oils may trigger an asthma attack. Essential oils emit strong odors that contain volatile organic compounds (VOCs) that pollute the air and can irritate the airways.”

Are evaporative humidifiers healthier than ultrasonic?

Any humidifier can have positive health impacts if they are used as directed. “A humidifier can benefit people with dry skin, respiratory issues, colds, chronic bronchitis or sinusitis or those living in dry climates with low humidity,” McKeon says.

Evaporative humidifiers have the advantage of using filters, which helps avoid the white particles that can settle when using an ultrasonic humidifier. “The biggest difference is that evaporative humidifiers are a mist-free humidification,” Thornburg explains. “The white dust from ultrasonic humidifiers is avoided, making it more hygienic.”

But the U.S. Environmental Protection Agency warns that any humidifier can release biological contaminants if they aren’t cleaned frequently and properly, so be sure to follow the cleaning instructions for the product you choose.