Why’s There Water on My Windows?

Water or frost on windows is condensation. Condensation forms when warm moist air comes in contact with cooler dry air just as a bathroom mirror will “steam up” after a hot shower. The inside or outside of your window can sweat or fog because of temperature differentials.


Should I Replace My Windows?

Faulty windows don’t cause condensation. Glass is usually the place you first notice condensation because glass surfaces have the lowest temperature of any of the interior surfaces in the house.


Then What’s the Causing the Moisture?

The moisture in the air causes condensation. The reason you may observe more condensation in your home is due to modern energy efficient home building techniques and products.


The insulation and construction materials used today are designed to keep cold air outside. This is especially true of new windows. While energy efficient designs and weather stripping keep cold air outside, they also keep warm moist air inside. Older window designs were less efficient and consequently allowed moisture to escape.


If you didn’t have as much condensation before replacing your old windows, it’s likely because they were drafty. Good windows and insulation all create barriers to the air exchange of a home. When combined with the additional water vapor (moisture) from showers, cooking or from clothes dryers not vented to the outside, the result is excess moisture and a high relative indoor humidity level.


Are There Ways to Reduce Condensation?

The key lies in controlling the humidity inside your home. First, let’s understand how the moisture forms. During the hot, humid summer, your house absorbs moisture. The same principle applies to a newly constructed or remodeled home, due to the abundance of moisture from the building materials used in construction.


During the beginning of the winter when you start to heat your home, condensation occurs. After a few weeks, your home will begin to dry out and you’ll see less condensation. Opening a window briefly is a quick temporary solution. The dryer, cold air will enter the room while moist air is allowed to escape.


Other steps to sake include:

-Cracking open a window or door daily to ar out your house

-Opening a window or running exhaust fans longer in the kitchen, bathroom and laundry room

-Opening drapes and blinds, allowing air to circulate against windows

-Turning off any humidifying devices in your home

-Installing and using a dehumidifier


If you live in a northern climate, the above, as well as the following points, may be relevant:

-Adding storm windows or replacing existing single-pane windows with insulated windows

-Keeping plants in a sunroom, or in rooms that aren’t frequently used during cold weather

-Adding waterproofing protection to basement floors and walls

-Removing radiator pans until sweating eliminates

-Making sure that open-faced gas heaters are connected to a chimney and using them as little as possible


When Should I Look into Replacing My Windows?

Window condensation should only occur during extreme temperature differences and should be of a reasonably small amount. During the winter months, the condensation you see on the inside of the window. Condensation will present itself on the outside of the window during the summer months.


If you find condensation between the two layers of glass in an insulated window, the airtight seal has probably broke and the glass may need replacement.


If there is too much moisture inside the home, you will find evidence during both the cold and warm seasons. Moisture spots on the ceiling or walls, peeling paint, rotting wood or delaminating plywood, moisture on exterior walls, fungus, mold or mildew growth are signs of a more severe moisture problem. Should you experience these symptoms, contact an expert heating and cooling contractor to solve your problem.