If your double glazing has started to fail — whether it's misting between the panes, a broken handle, or a draughty seal — one of the first questions you'll ask is: how much will it cost to fix? The good news is that many double glazing problems can be repaired at a fraction of the cost of full replacement.
Typical Repair Costs
Here's a rough guide to common double glazing repair costs in 2026:
- Misted / failed sealed unit replacement: £60–£120 per unit (depending on size)
- Window handle replacement: £30–£60 per handle
- Window hinge replacement: £50–£90 per hinge pair
- Window lock repair/replacement: £40–£80
- Rubber seal replacement: £5–£15 per metre
- Door lock mechanism (multipoint): £120–£250
- Door alignment / adjustment: £60–£120
These are guide prices — actual costs depend on the specific parts, access requirements, and number of items being repaired. We always provide a fixed quote before any work begins.
Full Replacement Costs
When repair isn't viable — for example, if UPVC frames are cracked, warped, or at the end of their lifespan — full window or door replacement becomes the better investment. Typical costs include:
- UPVC window replacement: £350–£800 per window (supply & fit)
- UPVC door replacement: £500–£1,200 (supply & fit)
- Composite front door: £800–£1,800 (supply & fit)
- Full house window replacement (3-bed semi): £3,000–£6,000
When Should You Repair vs Replace?
Repair is usually the right choice when the frames are in good condition and only individual components have failed — a misted unit, a broken handle, a worn hinge, or a degraded seal. These repairs typically cost a fraction of full replacement and can add years of life to your existing windows.
Replacement makes more sense when frames are severely damaged, windows are 25+ years old, energy efficiency is a concern, or multiple components have failed simultaneously. Modern UPVC windows offer significantly better insulation, security, and noise reduction than older units.
At Restoration Glazing, we offer both services and will always give you honest advice on which option makes the most sense for your situation. We never push unnecessary replacements — but we won't recommend a repair if it's only a short-term fix.
Factors That Affect Cost
- • Window size: Larger units cost more for both glass and frames
- • Glass type: Standard vs low-e, self-cleaning, or acoustic glass
- • Access: Ground floor is cheaper than upper floors requiring scaffolding
- • Quantity: Doing multiple repairs or replacements in one visit is more cost-effective
- • Frame condition: Minor frame repairs add cost; severe damage may necessitate replacement
Frequently Asked Questions
How much does it cost to repair a misted double glazed unit?
Misted or failed double glazed unit replacement typically costs between £60 and £120 per unit, depending on size. This replaces the sealed unit within the existing frame — much cheaper than replacing the whole window.
Is it cheaper to repair or replace double glazing?
In most cases, repairing individual components is significantly cheaper than full window replacement. However, if frames are severely damaged or windows are 25+ years old, replacement may be the more cost-effective long-term investment.
How much does a full double glazed window replacement cost?
A full UPVC double glazed window replacement typically costs between £350 and £800 per window, depending on size, style, and specification. This includes supply and installation.