What Causes Window Condensation and How To Reduce It?

There are a wealth of problems that cause condensation on windows.

Here at Chameleon, we have years of experience solving window condensation in period homes. Period homes experience condensation far more than modern homes for several reasons. Still, most commonly, it is because the windows require repair, restoration and secondary glazing. Chameleon is experts in restoring timber windows, and today, we’re looking at how this can reduce condensation problems in a period home.

Window Condensation Solutions

There are many solutions to window condensation. Still, many solutions only treat the problem, not the cause of the problem. Many damp and mould experts will say that investing in a dehumidifier will help to combat condensation. They do remove the moisture from the air in your home. However, if your windows allow cold air into the home, it can never eliminate condensation and other mould issues altogether.

Timber windows restoration

Sash windows renovation is one of the best ways of eliminating condensation altogether. If your sash windows have air gaps between the timber frame and the glass, this allows cold air into your home, which increases the likelihood of condensation. If you replace sliding sash windows this will prevent air from getting it, sealing up any air gaps and creating a good seal between the inside of your home and the outside.


Most of our sash windows renovation services involve draught-proofing the frames again. Whether we are installing double glazing into your sash windows or restoring parts that have rotted away due to condensation and other damp issues, draught-proof is always done to prevent these issues from returning.

Double glazing

A great way to reduce condensation problems altogether is to install double glazing into your sash window. This creates a thermal barrier that can stop condensation from forming on the inside of the window because the secondary pane of glass keeps an even temperature between the inside and outside of the home. Chameleon is experts in installing double glazing in sash windows. This is a huge part of our timber windows restoration services.

What causes the problem of condensation?

Timber windows, like sash windows, are very prone to condensation. This is because there is only one layer of glass protecting the home from outside temperature changes. So, when the temperatures inside and outside your home don’t match up, the water vapour in the air will cool as it hits the glass and forms condensation. Condensation on either the inside or outside of a period home can lead to damage to your windows. If the water pools on the timber, this can lead to rot and mould.

A lot of window companies will tell you to replace all of your windows with uPVC windows, but this isn’t necessary at all. Timber windows can be restored. Chameleon restored thousands of timber windows every year. We can remove any rotten timber caused by condensation and replace it with fresh timber. We can also draught-proof your windows and install double glazing that will prevent condensation going forward. By restoring your timber windows, you can keep the beautiful character of your home a prevent condensation from forming on windows, as well as and other damp issues.

Preventing window condensation

To prevent condensation from forming on windows, you must find the cause of the issue. You can buy dehumidifiers and all sorts of other modern gadgets to help you get rid of the damp inside your home. However, if your windows are not correctly installed or have draught issues, the condensation will always return. Finding a good balance between natural airflow, heating and cooling, is the only way to reduce condensation problems in your home (Source)

To find out more about condensation in period homes and how restoring your timber windows can solve the issue, please check out our FAQs about wooden window renovation.