Unified Home Remodeling

Why Window Condensation Happens (and How to Fix It)

Window condensation accumulates on a pane of glass.

Have you noticed that the windows in your home are continually fogging up? Believe it or not, window condensation is a common problem.

The weather is finally starting to warm up and you may have noticed your windows are not as clear as they once were. It’s not fun to peer through hazy windows at the Huntington Bay or the East River. While it undoubtedly creates an unpleasant aesthetic, window condensation oftentimes isn’t an indicator of a serious problem that you might think.

That’s especially true if more than one window is showing condensation, it is extremely unlikely that the seals are bad on all of your windows. Before we discuss how to reduce condensation, it’s important to understand what it is and why it happens. 

What is condensation?

Condensation is when water droplets collect on a cold surface because there is humid air in contact with it. It often occurs on windows because their surfaces are colder than the walls with insulation.

Why does window condensation happen?

Window condensation occurs in homes with too much humidity. It doesn’t matter if your house is old or new – or even if your windows are old or new. When the humidity inside your home is higher than the humidity outside, your glass windows and doors will start to show condensation.

Think about it. You likely aren’t surprised (or concerned) when your bathroom mirror becomes foggy after a hot shower. Or when your car windows fog up in humid weather or in the winter when you have several passengers in your car.

While we tend to think more about condensation in colder weather, condensation is especially common during the spring when evening temperatures across much of the northeast hover around 40 degrees.

How do I diagnose the problem?

To reduce condensation on windows, you have to first identify where the condensation is occurring. Is it on the inside of the window? The outside of the window? Or between the window panes?

Inside – Before calling your local repair service, run your finger through the area where the condensation is formed. If your finger gets wet and leaves a trail through the condensation, it’s on the room side of the glass. That is an immediate indicator of excessive indoor humidity.

Even if you aren’t running a humidifier, everyday activities like bathing, cooking, and even breathing contribute to the humidity in your home (You can stop holding your breath now). While new windows and doors create a tight seal, it also means your home will retain more humidity.

Note: Think of condensation on your windows as an indicator to reduce the humidity in your home before bigger issues occur.

Outside – Exterior condensation generally occurs in the summer months when outside humidity levels skyrocket. You’re most likely to see it when there is high outdoor humidity, little or no wind, and a clear night sky – and you’ll typically only see it in the morning after a cool night. As the sun shines and begins to warm up the glass, the dew on the outside of your windows will evaporate.

In Between – A seal failure is the primary reason why windows fog between the panes. A leak in the seal allows moisture to seep in between the glass. If you notice condensation between the glass of your window, it’s probably time for a window replacement.

Contact us at (888) 631-2131 or visit www.unifiedhomeremodeling.com to schedule a FREE estimate to replace your windows that may have condensation.

Condensation on the window turns to frost in cold weather.

What kind of problems can condensation cause?

While the condensation itself isn’t necessarily indicative of a problem, it may be an indicator that you need to reduce indoor humidity before it causes hidden, costly problems elsewhere in your home.

Excessive humidity can cause serious health problems because mold and mildew thrive in moist areas with plenty of organic materials, such as wood, plaster, and insulation. When inhaled or ingested, molds are known to cause local or systemic allergic reactions, sinus and nasal irritations and infections, chronic respiratory problems, dizziness, and trigger attacks in people with asthma.

Humid indoor air can also cause the insulation to deteriorate; paint to blister and peel; unsightly stains on walls and ceilings; rotting of floors, wall supports, and other structural supports; and foundation damage.

How do you prevent it?

Springtime is among the wettest seasons of the year, so be sure to check your moisture levels often. As the humidity rises outside, a house that doesn’t “breathe” properly will be susceptible to a number of problems.

  1. Increase circulation – Air circulation is key, so open up the windows. Leave interior doors open throughout your home to prevent humidity from building up in one space. And use those ceiling fans. Even in the winter, your ceiling fans will help move air around and push warm air down from the ceiling.
  2. Check insulation – Because condensation is caused by heat and moisture, it’s a good idea to make sure your home is insulated to make the air easier to control. Insulation can be as simple as weatherstripping and door sealing. Wall and attic insulation will also help prevent humidity build-up in your home. If you’re not sure how your home stands up against humidity call (888) 631-2131 or schedule a FREE estimate at www.unifiedhomeremodeling.com with one of our home experts.
  3. Use a dehumidifier – Dehumidifiers help extract water from the air. They are often used to eliminate musty odors and prevent mildew, mold, and bacteria; but dehumidifiers can also be used to reduce condensation on windows.

Consider foggy windows as a warning sign and take action right away to avoid potentially expensive repairs and hazardous breathing conditions in the future.

And if you decide you’re in need of new windows, doors, siding, roofing, or anything else for the exterior of your home… well, you know where to find us.

Request A FREE Estimate

    Scroll to Top