How to Know Whether it is a Leak or Condensation

Geek Level 1

Have you begun to notice water on your window? It could be a leak, or perhaps the cause is condensation. If it’s the latter, that is not necessarily a bad thing.

Your priority should be to work out whether or not it is condensation. Once you have, you can determine if it’s normal or the sign of a problem that needs to be addressed.

How do I know if it’s a leak?

One of the best telltale signs of whether you’re seeing a leak or condensation is the location of the water. If it’s beading on or fogging up the glass, that’s almost certainly condensation unless it’s coming in from the top. If it’s not on the glass but on the seal or the frame, your window is likely leaking.

Is the condensation on the inside or the outside of your window?

If the condensation is on the glass outside the home, there’s a good chance it’s simply climate-related and has something to do with the weather. If it’s cold outside, then the temperature difference caused by the heat inside your home may be the culprit. This can happen even if you have high-performance windows. They do their job so well, keeping the heat from escaping, that the outside pane remains cold and condensation subsequently collects.

If the condensation is inside, then consider where in the house you are seeing it. Have you been cooking, or just taken a hot bath or shower? Are you seeing it on mirrors too? If so, this has likely caused humidity to build inside, and subsequently resulted in condensation. This is easily fixed by improving the ventilation in your home, which can be as simple as popping open a window or turning on your extractor fan. Make sure you do this to prevent mould issues from occurring over time.

What if the condensation is between the panes?

Noticing condensation between the panes is the biggest cause for concern. The space between is supposed to be air-tight, and if there is condensation, then something has gone wrong and that seal has broken somewhere.

Top tip: Don’t let problems get out of hand. We recommend inspecting your windows on a regular basis so that any issues are caught early and are easier to deal with.

If you’ve noticed this problem, there’s little you can do besides getting the window serviced. The most likely outcome is that the window or windows in question will need to be replaced with new energy-efficient ones. We always recommend opting for superior quality, high-performance windows for the sake of longevity. You don’t want to be stuck replacing them again a decade or two down the line. This is where something like Centra’s lifetime warranty comes in particularly handy.

We are your certified Window Geeks

Centra Windows is not only the manufacturer but also the installer of its product, which enables us to offer a full warranty, eliminating any confusion between product performance and installation. We view the house as a system and understand how each of the elements must work correctly to maximize the comfort and energy efficiency of your home. Contact our local Employee Owners at 1-888-534-3333 or send us an email at for more information about this topic and many more. You can also sign up for our biweekly newsletter for all the tips and tricks about the window industry.

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