Can misted double glazing be repaired or does it need replacing?
If you’ve noticed a cloudy or misted window, it’s a common problem that can be worrying.
Homeowners often assume the worst: “Do I need to replace the whole window?” After 25 years fitting windows across Cheltenham, I’ve seen this a hundred times, and the answer isn’t always a full replacement.
Let’s break it down clearly so you know your options, the costs, and when it’s worth repairing — and when it’s time to bite the bullet and replace.
What causes misted double glazing?
Misted windows happen when the seal between the glass panes fails, allowing moisture to get trapped. You’ll notice it usually in the middle of the window, not on the surface.
Common causes include:
Age: seals can wear out after 10–20 years depending on quality and exposure.
Poor installation: if the window wasn’t sealed properly, it can fail early.
Accidental damage: knocks, cracks, or pressure can compromise the seal.
Can misted windows be repaired?
Sometimes, yes. There are a few options depending on the type of window:
Glass unit replacement: In most cases, you can replace just the double-glass unit without replacing the whole frame. This usually costs £120–£200 per window.
Hinges, handles, or minor frame repairs: If the frame or fittings are causing condensation or alignment issues, fixing these can extend the life of the window by several years.
Professional “de-misting” services: Some companies offer fog removal or seal repair, but results can vary.
The key is assessing whether the frame itself is sound — if it’s warped, rotten, or draughty, replacement is often the more reliable long-term solution.
When you should replace the window
Full replacement is usually the better choice if:
The window is old (15+ years) and multiple units are failing.
You’re noticing other issues like draughts, sticking, or condensation inside the frame.
Energy efficiency is important — new double glazing can significantly reduce bills.
How to avoid getting it wrong
Check if your installer is local and experienced – someone who knows Cheltenham homes will spot issues others miss.
Get a proper assessment – don’t just take a quick quote.
Ask about guarantees – a good installer will stand by their work, whether it’s a repair or a replacement.
Compare costs fairly – repairs are cheaper upfront, but sometimes replacement saves money in the long run.
Final word
Misted double glazing is rarely the end of the world. Often a repair is enough to restore your view, but sometimes a replacement is the smarter investment. The key is honest advice from someone who’s been fitting windows for 25 years — you don’t want to pay for unnecessary work or be sold a whole new house’s worth of windows when a repair will do.
If your windows are misted, draughty, or just not performing as they should, get in touch.
I can assess your windows across Cheltenham and give a clear, fair recommendation. Get in touch today.