We have a home humidifier sitting in the living room of the Brain household. It happens to be the older version of this model, which can put more than five gallons of water into the air each day. It’s big enough to handle the whole house, and the fan is not silent, so it is easy to notice it. A friend stopped by this week and asked why we use it.
This morning is a typical winter morning (at least this year) in North Carolina. It is bright, clear, 23 degrees F outside and very dry. If we were not using the humidifier, it would be bone dry inside the house – less than 20% humidity. That kind of low humidity would have at least three noticeable effects:
By using a humidifier, all three of those problems disappear.
You could either go with a whole-house unit, or smaller units in separate rooms. It is possible to get smaller humidifiers that are completely silent. Another possibility is adding a humidifier to your furnace, although that tends to get more expensive. The advantage is that you don’t have to refill the water every day, and it completely covers the whole house.
Why does the air get so dry in the winter? The air outside right now has 60% humidity according to our little weather station. 40% to 50% is the recommended level indoors. 60% sounds great, so what is the problem? When that cold air comes inside and gets heated, the humidity of the air changes dramatically. As shown on this page, “The amount of water vapour the air can hold increases with temperature. Relative humidity therefore decreases with increasing temperature if the actual amount of water vapour stays the same.”
If you want to make one yourself for a small space, try this video for a couple of ideas (putting a small fan nearby would amplify the effect):
You can also buy little ultrasonic fog units like this: