How to Fix Blown Double Glazing

How to Fix Blown Double Glazing

If you’re struggling to see through your windows and they always look misted, this could be a sign that your windows are “blown”. This is a term used to describe the build up of condensation between the panes of glass. 

When this happens, it might look like there is moisture on the inside or the outside, but when you wipe the glass you’ll notice that it doesn’t help. This is because the moisture is between the panes of glass and this happens because of a broken seal.

What causes blown double glazing?

To understand how double glazing fails, we first have to understand how it works. Double glazing has two panes of glass that are held together by the frame. Between the glass there is a vacuum that is maintained by a seal. This seal can either contain air, or argon, which is an inert gas with lower heat conductivity than air. This layer of air or argon helps to increase insulation by keeping a layer of warmer air between the panes of glass. This reduces heat loss through your windows.

When this seal between the panes of glass fails, this can make the space between the panes colder, which will attract moisture from the inside or the outside of your home. This becomes trapped in the panes and will condense on the glass, causing a misty appearance.

How do you fix blown double glazing?

How do you fix blown double glazing?

There are two ways to fix blown double glazing. The first is to repair the glass and the second is to replace it. To repair the glass, a small hole is drilled in the frame and then a desiccant material is inserted into the hole. This material will absorb any moisture and prevent it from building up again. The frame is then resealed to help prevent a repeat of the issue.

To fix a blown double glazing window with a replacement, you can just replace the glass part of the frame and leave the original frame intact. This is a great option if you want a quick fix that will reduce the risk that the problem will return. Once the glass has been replaced, your glazer will then replace the seals around the window to help create a watertight seal.

How much does it cost to fix a blown double glazing window?

How much does it cost to fix a blown double glazing window?

The cost will vary depending on the size of the window and the type of repair you choose. Replacing a very large window will be the most expensive option, while replacing a smaller window will be much less expensive.

If your windows are very old (installed more than 20 years ago) and you’ve noticed an increase in the number of issues you are having with your double glazing, it might be time to start thinking about replacing the windows and the frames. This will allow you to have a modern, updated look in your home, while also eliminating the chances of repeat issues with blown double glazing.

Closing thoughts

Blown double glazing or misted double glazing is a common problem in ageing windows. There are multiple options to choose to fix the issue, including repairing or replacing the glazing. If your windows are nearing the end of their life, it could be time to think about replacing your windows and frames. 

The important thing to remember is that you shouldn’t leave this problem untreated, as this can lead to issues with your frames and brickwork due to a buildup of moisture. It’s also not a great look for your home and can damage the curb appeal of your house. Not to mention, you won’t be able to see out of your windows, which will make your home much darker.

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