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What Causes Film On The Inside Of House Windows?

By January 23, 2023No Comments
Be sure to read up on what causes film on your house windows.

When it comes to owning a home there are many maintenance needs and projects to be done. The moment that a homeowner notices film on the inside of their windows frustration can often settle in. Typically, this means that the seals or caulking around the windows are not working properly. The film, fog, and condensation in your house windows are frustrating because your view is blocked. What causes film on inside of house windows? Broken seals that allow moisture to enter the window’s double pane are usually the culprit.

Let’s take a look below at what the causes of film on your windows are.

What Causes This?

When you see film, fog, or condensation buildup on your windows it is typically caused by failed seals. Foggy or film buildup is a direct result of the insulated glass unit (IGU) seal deteriorating. All insulated windows use double panes of glass and have air in between the panes. The air that is used by the manufacturer is typically argon or krypton. Additionally, this gas increases the energy efficiency of your windows. The more energy efficient your windows are the more likely your temperature-controlled air is kept inside the home. Let’s take a look below at what can cause the window seals to break down.

  • Old age – windows are built to endure harsh temperatures and sustain constant opening and closing for many years. As time goes by the use of your windows will create a deterioration of the double pane window seals.
  • Exposure to water – if water is building up near your windows the seals can begin to break down. Be sure to check on the window seals after heavy rainstorms or even flooding.
  • Excess heat – if you live in an area where the warmer months have extreme heat conditions, the seals around the window panes will begin to stretch due to the expansion of the air inside the window panes. Direct sunlight can cause a deterioration of seals over a long period of time.

When the seals break down the moisture from the air that is escaping the window panes creates a foggy or film look.

Condensation on your windows should be fixed right away.

How Can I Prevent This?

The biggest way to prevent film, fog, or condensation in your windows is to have them installed properly. Let’s take a look below at other ways to prevent your windows from filming up.

  • Correct installation – hiring the right professional window installation company actually matters. Make sure to call around and ask questions about the level of experience and knowledge the window installation team has.
  • Get rid of moisture – in most cases, using a dehumidifier will remove excess moisture from your home and keep that air from getting into your window panes.
  • Ventilate your home – creating good circulation in your home keeps warm air from sticking to your windows and creating a film.
  • Purchase energy-efficient windows – losing heat or gaining heat through your windows can make up between 25% and 30% of your home’s energy usage. Also, check to see if your windows have a lifetime guarantee from the manufacturer.
  • Add window protection – adding a film to your windows will help regulate the temperatures of the windows. Additionally, the film can prevent moisture from getting between the windowpanes.
  • Inspect your windows – taking the time to look around your windows every couple of months ensures that all seals and window framing is intact.

Other Recommended Maintenance

Now that you understand what causes film on your house windows, you can read up on why your windows might leak when it rains. Understanding the ins and outs of your windows is important. It is possible that you purchased a home that needs to upgrade the windows. Also, you could end up seeing another simple solution as replacing the caulk seals around your window frame. No matter the reason, getting your windows inspected for leaking and condensation can go hand in hand.

Next, increasing natural light in the home is something that many homeowners choose to do. Natural light can reduce your electric bill. Be sure that furniture or drapes aren’t blocking the natural light from coming in.

Lastly, there is so much to learn about windows depending on the type and style that is in your home. Every window is designed a little bit differently as each manufacturer tries to put their spin on window design. Always remember to read the manufacturer’s instructions on how to clean and maintain their products. In this case, how to clean a double-pane window.

Call a professional to help with foggy windows.

When Do I Call A Professional?

If your windows have a film inside of them, it is likely caused by moisture getting into the window. Additionally, it could be something as simple as your ac temperatures being too cool compared to the outside air. Consequently, hire a professional window installation company to come out and re-seal your windows and caulk the frames. This should correct your issues. Also, reach out to your local home inspection team so that they can inspect all of your windows for other possible damage. Additionally, they can refer a reputable professional window installation company to help with this project.


Once you notice that your windows have a film on them, you should consider adjusting the moisture levels in your home. If this doesn’t take care of the problem then you should call on your local home inspection team. They can inspect all of your windows and recommend any necessary repairs. Reach out to Avalon Home Inspectors to check your windows when inspecting your home in Atlanta, GA., and surrounding areas.

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