What is happening
Outdoor air in a Connecticut January holds very little water. When it leaks into the house and warms up, its relative humidity drops sharply, often into the teens or low twenties. The more outside air the house pulls in through gaps, the drier it gets.
What level to aim for
Somewhere around 30 to 40% indoor humidity is comfortable for most people. On the coldest days, aim lower. If water forms on the inside of the windows, the humidity is too high for that outdoor temperature.
A basic hygrometer from a hardware store will tell you where your house actually sits before you spend anything.
What a whole-home humidifier fixes
A humidifier mounted on the furnace adds moisture to all the air the system moves. It ends the static shocks, eases dry skin and sinuses, and protects wood floors and trim. A modern unit adjusts its output to the outdoor temperature so the windows stay clear.
What it does not fix
- Houses without ducts. A whole-home humidifier needs forced air. Boiler-heated houses need room units or a different approach.
- Drafts. If the house leaks badly, a humidifier works hard and still loses. Air sealing is often the better first spend.
- Mold or musty smells. Those are a moisture problem, not a dryness one, and a humidifier can make them worse.