Why Are My Windows Foggy?

Have you ever noticed, especially during the winter, how fog builds up on the windows of your home? As kids, many of us drew pictures and wrote notes in that fog during snow days to alleviate the boredom. When we stopped to ask about it, “condensation” was our answer.

Sometimes we’d even get a neat weather demonstration. However fun that was, it didn’t always clear up the proverbial fog when it came down to the window itself. Below, we’ll go over the science of condensation and give pertinent examples for everyday life for a complete answer to “Why are my windows foggy?”

The Science Behind Condensation

Molecules are always in a state of motion. At different temperatures, their rate of motion changes. For example, the colder water molecules become, the slower they travel. The slower they travel, the closer they become. As they group together – condense – their physical properties change drastically.

When the water molecules in the air become dense enough, they form minuscule droplets. The transition from a gas into a liquid is complete. Your windows are a prime location for this to take place.

The Water Cycle on Your Window

The science of condensation comes into play whenever there is a change in temperature, especially when dealing with warmer air, which can hold more moisture. When the interior of your home is a drastically different temperature than the exterior, condensation will most likely occur. It is also common when there is excess humidity in your home.

Warmer air is able to hold more moisture and it is drawn to the coolest surfaces in your home, which tend to be windows and doors. As the warmer water molecules in the air come into contact with the cool glass of windows, they slow down and group together becoming visible moisture. To the naked eye, this looks like fog.

Temporary Condensation

However natural the process is, it should be temporary. Temporary condensation is generally not a cause for concern. You’ll usually see it pop up on bathroom windows during baths and showers or kitchen windows during cooking or dishwashing. If you have a laundry room with windows, you may even see those windows fog up a little when you’re doing laundry.

Sharp temperature changes and the start of the heating season can also cause temporary condensation on windows. With properly insulated windows, you’ll often see condensation appear at the bottom since cooler air within the window sinks towards the bottom of the glass.

Permanent Condensation

If condensation on your windows sticks around well after these activities and after the temperature levels out, you may have permanent condensation on your hands – and that is a cause for concern.

If you see that your windows are still fogging up despite being well into winter, you may have a problem. Either your home is too moist, requiring a dehumidifier, or your windows need to be replaced. If windows aren’t correctly installed or insulated, they can’t fight condensation. As innocuous as it seems, condensation can cause some serious water damage and mold growth over time.

If you’re worried about your windows, call Zephyr Thomas at 717-399-4708 or stop by for a free consultation. We know windows, and we’d love to help.