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Foggy Windows Could Equal High Indoor Humidity

Foggy windows during the winter can be a sign that your windows are drafty—or that you have too much humidity indoors.

If you wake up to frost on your home’s windows, chances are good that your house is a bit colder than it should be. And that means you’re cranking up the thermostat too high.

Condensation on windows could mean they’re not keeping the cold air out. Moisture in the air condenses when it touches a cold surface, causing the glass to sweat like a cold glass of iced tea on a hot day. Condensation can form on the glass and even pool on the windowsill. And like any excess moisture, it can eventually lead to mold and mildew.

That can damage your window frames over time.

Consider replacing drafty, single-pane windows. Double-pane windows are more energy efficient. Or add an extra layer of glass by installing storm windows.

And get rid of as much of the humidity inside your home as you can. Here’s how:

  1. Install ventilating fans in every bathroom and turn them on before every shower. Let the fan run until the “fog” clears out of the bathroom, but no longer. Overuse of exhaust fans can send your home’s comfy, air-conditioned or heated air right out of the house.
  2. Use the hood fan over your stove when you cook. Cooking sends moisture into the air—along with lingering odors. The fan will rid your home of those smells and humidity. Again, run the fan just long enough to clear the air.
  3. Vent your clothes dryer to the outside. Check the duct for leaks, especially at the point where it’s attached to the dryer, and for obstructions that can prevent hot dryer air from escaping to the outdoors.
  4. If you run humidifiers inside the home, don’t overdo it. It’s possible to add too much moisture to indoor air.