The Best Whole-House Humidifiers for Healthier Indoor Air

The Good Housekeeping Institute has provided expert reviews and advice on HVAC equipment for decades. In the last two years, our engineers and product analysts in the Home Improvement & Outdoor Lab evaluated dozens of humidifiers, including hands-on testing of 20 console humidifiers in our most recent Lab review, during which we assessed factors like moisture output, ease of use and noise level.

While we haven't conducted side-by-side installation of whole-house humidifiers, we relied on our expertise in testing HVAC equipment to help drive our research and recommendations. We also consulted the Building Performance Institute, which trains and certifies professionals who specialize in creating healthy, safe and efficient homes. The picks featured in this roundup are from brands that have performed well in previous tests.

✔️ Type: There are two types of whole-house humidifier: integrated and freestanding. Here's what you need to know about each.

• Integrated: These systems are designed to work with a home's existing forced-air heating system. They tend to cost more and require professional installation, but they do the best job of humidifying all the air in the home as it circulates through the system, plus they can be programmed to work automatically.
• Freestanding: Also referred to as console humidifiers, freestanding units portable and doesn't integrate into your home's HVAC system. Nevertheless, these units can feature a large capacity and are a great choice for smaller homes or apartments.

✔️ Technology: Different technologies are used to add moisture to the air in a home. Here are the main types:

• Evaporative: These units, which can either be integrated or freestanding, use a fan to blow air through a wet wick or filter, evaporating water and increasing humidity. They are energy efficient and work well in very arid climates.
• Bypass: These integrated systems divert warm air from the home’s HVAC system and pass it through a wet pad, then send the humidified air back into the home. They’re a cost-effective solution but have limited coverage area, so they’re best for smaller homes, say, 2,000 square feet or less.
• Fan-powered: These integrated systems use a fan to blow air over a wet surface, adding moisture to your home. They’re energy efficient and have large coverage areas.
• Steam: These integrated whole-house humidifiers have a reservoir attached to the furnace where water is turned into steam and released into the air. They’re good at raising humidity levels quickly. “Smart” versions use sensors to read humidity levels in the home and only add moisture as needed, making them more energy efficient than systems that run constantly.

✔️ Coverage area: Make sure you purchase a whole-house humidifier that meets your specific needs. "The size of your home, the type of existing HVAC system, the climate zone you are in and your economic circumstances should all be considered to determine which of the different systems makes sense," says the Building Performance Institute's Amanda Hatherly.

If your house is 2,000 square feet, you don't need a whole-house humidifier that can cover up to 5,00 square feet. Evaporative, bypass and even freestanding humidifiers are ideal for smaller to medium-sized homes, while fan-powered and steam humidifiers are an excellent choice if you have a larger coverage area.

✔️ Tank capacity: A whole-house humidifier's tank capacity refers to how much water it can store in the unit at a time. The larger the tank capacity, the more efficient the machine will be at pumping moisture into your home's air. This is especially important if you're purchasing a freestanding unit since a larger tank capacity means fewer refills.

✔️ Humidistat: This device monitors the air in the home and turns the system on automatically when humidity levels drop below a certain level. The humidistat will also turn the system off automatically, preventing moisture and condensation from building up in the home. Without a humidistat, our experts say you’ll need to monitor humidity levels in your home with a hygrometer and operate the humidifier manually.

✔️ Run time: Whole-house humidifiers that integrate into your HVAC system are able to run constantly, which is what makes them so appealing if you have a seriously dry home. But if you opt for a freestanding humidifier, you'll have to pay attention to its run time as it will only operate as long as there's water in the tank. Most consumers will prefer an efficient humidifier with the longest run time, meaning that it has a larger tank and requires fewer refills.

The average cost to add a whole-house humidifier to your home is around $580, according to ANGI, the home services marketplace. That includes the cost of the equipment, as well as professional installation Larger systems might run as high $1,350. Whole-house humidifiers also need to be professionally serviced, usually once a year for between $100 and $200. The Building Performance Institute has a searchable database of certified professionals to assist with the project.

This investment is much greater than that of a single-room console humidifier, which can cost as little as $50. Keep in mind, however, that you might need four to five console humidifiers to do the work of a whole-house system, and even then the coverage and performance of the smaller units won't be as effective.

Dan DiClerico has been testing and writing about humidifiers for 25 years. In that time, he has spearheaded numerous investigative reports on the topic of indoor air quality, working closely with outside experts from government, industry and the home services space. As Director of Home Improvement and Outdoor at the Good Housekeeping Institute, DiClerico oversaw the latest round of humidifier testing in our Labs, as well as the continuous in-home, survey-based consumer testing that allows us to evaluate these devices in real-world conditions.

Olivia Lipski covers everything from consumer electronics to home, outdoor, fitness and more. To survive harsh NYC winters (and the dry skin that comes along with it!), she’s been sleeping next to a cool mist humidifier for years.