Evaporative home humidifiers are the most popular types of home humidifier systems. These systems are available in tabletop portable models, as central humidifier systems or as units which can be added to a normal blower vent in any room. Evaporative home humidifiers also tend to be less expensive than other costly systems, such as ultrasonic humidifiers and spray mist systems.

How Evaporative Home Humidifiers Work

The mechanism that drives evaporative humidifiers is simple. Air is passed through a wet medium, such as a fabric, foam or aluminum wick filter, grille or pad. The air picks up moisture from the pad or filter through evaporation and carries it into the room. Evaporative humidifiers can come outfitted with their own fans or they can use forced air from an HVAC system.

Advantages of an Evaporative Home Humidifier System

Evaporative systems are very reliable, as the only moving part required is a fan. The filter system also helps remove minerals and impurities present in hard water, which helps prevent the notorious “white dust.” White dust, as described by the EPA, is particulate mineral and microorganism matter that is dispersed by humidifiers and settles on surfaces. White dust can be harmful if inhaled. Evaporative humidifiers also use very little electricity.

Disadvantages of an Evaporative Home Humidifier Systems

Evaporative home humidifier systems are more susceptible to mold growth and mildew buildup on the wet medium, particularly when it is kept moist around the clock or has standing water in the system. Because of this, wick filters must be changed regularly and the system must be cleaned to prevent bacteria growth. This adds cost and upkeep. In general, wick filters must be replaced once every two months. However, this varies depending on water hardness and other circumstances.

Other Considerations

Evaporative humidifiers are referred to as “cool mist” humidifiers. Unlike warm mist humidifiers, evaporative units do not have a heating element. An evaporative humidifier may make the room feel cooler because of this. The fan in an evaporative humidifier can also be noisy, so look for a humidifier with an adjustable fan setting. You can keep the fan on high during the day and then turn it to a lower setting when you are trying to sleep. In general, evaporative humidifiers also have higher outputs than warm mist humidifiers, but check the specifications on the box to compare models.

Overall, evaporative humidifiers are affordable, portable, reliable and relatively safe. As one of the top cool mist humidifier types, evaporative humidifiers are one of the most common types of humidifiers you’ll find.