How to Fix a Window Leak at Home

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Noticed that one of your windows is leaking? Don’t panic!

First, you should determine whether your window is actually leaking. The water you’re seeing could simply be condensation, and that is not necessarily a bad thing. Once you’ve ruled out condensation, you should try to work out the cause of the leak and where exactly the water is coming from. If the rain has stopped, using a hose is a quick and easy way to find out.

It’s also worth trying to find out whether the window is allowing water to leak in to the wall below, which can cause considerable damage.

What is the cause?

When you’ve pinpointed the area, it should be easier to figure out why the window is leaking. It could be down to general wear and tear, or perhaps you went with a company other than Centra and the installation job has been done poorly. Don’t worry. We still love you.

More often than not, the window seal or locks have simply degraded over time. If your windows are older, this is almost certainly the case. If your windows are newer and you can’t find any issues with the sealant or locks, it is likely to be an installation issue or a design flaw. There could be gaps in the flashing, or perhaps the windows are just ill-fitting.

Is there an easy fix?

If the issue is down to damaged sealant, we would suggest saving yourself some money and doing a spot of DIY. It’ll be a lot cheaper to head down to your local hardware store and get some new sealant. When the rain has stopped and there’s a dry spell, remove the old, damaged stuff. Clean the area, and apply the new sealant evenly. Once it has had time to set, the problem should be solved. You can also replace the gaskets and weather stripping on the frame so they are both air and water tight. If the issue is the lock then things can be a bit more complicated, but it may still be possible to repair or replace them yourself.

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 there’s an installation issue or design flaw, contact your installer, or if you don’t have a warranty, bring in a professional to undertake repairs. Attempting to fix the window yourself could lead to even more trouble.

Think about it this way: Your leaking window is a problem, but it’s not THE problem. Moisture buildup on your windows is a symptom to something more significant. The longer you postpone replacing your windows, the bigger the chance the leak will generate a major issue.

How does Centra prevent leaks?

Having operated in beautiful (but rainy) BC for almost four decades, Centra knows a thing or two about preventing leaky windows. Because we manufacture our windows locally, we can build them for the local climate, which is one of the wettest in the world. We test our windows using a device that is able to simulate a category 1 hurricane. It puts the windows through the equivalent of 8 inches of rain per hour and 120km winds. Thanks to this process, we can ensure the windows going into your home will be leak-free. Hooray!

Top Tip: Keep the drainage paths clean. These areas can fill up with junk and debris so flushing those out with a bottle of water will ensure the drainage path will do its job during the next rainfall.

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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