January 2018

Why is there condensation on my new double glazed windows?

We get many calls from our customers about condensation on their newly installed windows. Although this is often an unwelcome addition to your new double glazed windows, this is a great sign that your new windows are doing a great job of preventing heat loss.

One of the most popular reasons to replace your windows is to make them more energy efficient. Condensation doesn't usually get the opportunity to form on older inefficient windows as there is too much air flowing through the frames. This is often the reason that the windows have been replaced in the first place.

What causes the condensation?

Condensation has different causes depending on whether it is on the inside or outside of your windows. Internal condensation occurs due to the water vapour inside your house having nowhere to go. The vapour is generated through many everyday things such as your bathroom activities, cooking, boiling the kettle, drying clothes and even breathing. To put in perspective how much vapour is produced, on average each person in your household adds around 1.5 pints of water vapour through breathing alone and that is before you add around 2 pints per bath or shower, 6 pints average through daily cooking and kettle use and around 9 pints per day if you dry clothes indoors.

By airing your rooms for around 15 minutes per day you should exchange the air and reduce the build-up of moisture in your home enough to reduce internal condensation dramatically.

If you are getting condensation on the outside of your windows you are much less likely to be able to control this. This is more likely to happen during changes in the climate and quite likely to only appear on some of your windows due to their location. External condensation is an excellent indicator that your windows are preventing heat loss from your home - which means you should be getting reduced energy bills. Maybe we should start to see external condensation as a little reminder we are saving a few more pennies again this month.