When in heating mode, people are confined indoors with unusually dry air for many months each year. Humidifiers help the right comfort level of humidity, and properly maintained levels of humidity are beneficial for your respiratory system. Whole-house humidifiers work like your more typical room humidifiers. They distribute moisture into the air, making harsh, dry air much easier to breathe. And whole-house humidifiers add humidity throughout the house, no more moving a humidifier from room to room, spilling water on the floor as you go.