Is The Sealed Insulation In Your Windows Failing?

Posted on: 31 July 2015

Sometimes it's easy to see that your windows are in need of repair or replacement. If your latest newspaper delivery sailed straight through your front window with a big crash, there's no doubt at all that it's time for a new window (and maybe a different newspaper subscription). But if you've got double-glazed or triple-glazed windows, you also have to know how to tell that the seal around the glass is failing.

What Does The Seal On Glazed Windows Do?

Double-glazed windows use two panes of glass; triple-glazed windows use three panes of glass. These multiple panes are sandwiched together, and in between them are thin layers of gas. This gas may be simply a sealed pocket of air; sometimes, this air is replaced with a noble gas such as argon or krypton. In either case, these thin layers are used as insulation, slowing the transfer of heat through the window. If this sealed space is breached, however, it loses this insulating property.

How Can You Tell If A Seal Has Failed?

Windows generally have an expected lifespan. One thing that you should do is check the warranty for your windows and see how long it is; this will give you a sense of the manufacturer's expectations for the seals. If your windows are reaching – or past – the end of the warranty, you'll want to check them more frequently for problems. If the windows are relatively new, on the other hand, that doesn't mean that the seal can't have failed; storm damage, poor installation, or even shifting and settling of a building's foundation can affect the seal.

To check individual windows, look for condensation between the panes of glass. A proper seal leaves no way for moisture to get inside, so condensation is a clear sign that this seal has failed. When checking for condensation, it's a good idea to clean the inside and outside of the windows and thoroughly dry them so that you're sure you're not mistaking external water for internal condensation.

What Should You Do Next?

If you have double-glazed or triple-glazed windows, it's probably because insulation is very important to your home – perhaps you live somewhere with very cold winters. You'll want to get your windows replaced as soon as you can, and if it's not yet winter, certainly it should be done before the weather gets colder. Without this added insulation, you may see your heating bills increase dramatically depending on the number and size of failing windows.

For more information about window replacement, visit