Many people ask me what the proper humidity level in their home should be. While the humidity level each home can handle varies based on the home’s insulation level, window quality, and outdoor temperature, the ideal humidity range is 30-55% relative humidity. Achieving proper humidity levels is very important for your health and keeping your home in good condition.
Humidity levels that are too low are uncomfortable (dry, itchy skin), can be unhealthy to asthma and allergy suffers, will warp and crack wood and furniture, and can result in higher heating bills. Low humidity levels make you feel colder so you compensate by setting your thermostat higher and increasing your heating bill – it’s not the heat it’s the humidity! It can also increase moisturizer and lotion bills!
On the flip side, humidity levels that are too high can promote mold, bacteria, virus, and dust mite growth, can also be bad for asthma and allergy suffers and will also damage wood. During the winter, high humidity levels will also lead to condensation on windows which can lead to mold growth or water damage.
In the summer your air conditioning system will dehumidify your home, often pulling gallons of water out of your air every hour! Sometimes a stand-alone dehumidifier may be necessary, especially in musty basements. In the winter, your home will need a humidifier to add humidity to that dry winter air. Your humidifier is most commonly hooked up to the “humidistat” which is a dial or digital display on your wall or return ductwork which will allow you to control the humidity. A whole-house humidifier that is tied to your ductwork will be the healthiest and most effective humidifier. Watch out for stand-alone humidifiers that have standing water which could promote bacteria growth.
When setting the humidity in the winter, I always recommend to set the humidistat to the highest humidity level the home can support (up to 55%). Remember, higher humidity levels are healthier and lower utility bills because they are more comfortable. However, as it gets colder outdoors, the windows and window frames of your home will also get colder and you may get moisture condensation and even frosting. This is a sign that your home can’t support that level of humidity and you will need to lower the setting on your humidistat. Replacing windows or window frames with better insulated windows might also be something to consider down the road.
Stay tuned for the next posting which will discuss the different types of humidifiers and which one is best for your home.