Double Glazed Unit Replacement

If your double glazing has misted up, shows condensation inside the panes, or has a cracked sealed unit, double glazed unit replacement is often the most straightforward solution. At Window Repairs Sutton, we specialise in replacing failed sealed units in uPVC windows, restoring insulation and clarity without needing a full window replacement. Our 10+ years experience and public liability insurance ensure reliable service for local homeowners.

Who This Is For

Double glazed unit replacement suits homeowners noticing issues like misted double glazing, blown double glazing, or a cracked double glazed unit.

This service targets uPVC windows where the sealed unit has failed, causing poor performance or safety concerns.

If you’re in Sutton dealing with condensation inside double glazing or a failed unit, our DBS-checked technicians can assess and fix it efficiently.

Common Causes

Sealed units fail over time due to several factors. The most frequent is seal degradation from weather exposure, leading to misted double glazing replacement needs.

Physical damage from impacts causes cracked double glazed units, while manufacturing faults or extreme temperature changes contribute to blown double glazing.

Age plays a role too; units over 10-15 years old often develop condensation inside double glazing as argon gas escapes and seals weaken.

Related Symptoms

Spot these signs early:

• Misted double glazing: Fog between panes.
• Cracked double glazed unit: Visible fractures in the glass.

Likely Fixes & Options

The primary fix is sealed unit replacement, removing the old unit and fitting a new one matched to your frame.

We offer standard clear or low-E glass options for energy efficiency, or toughened glass for safety in accessible areas.

For failed sealed unit replacement, we prioritise quick swap-outs during a single visit, minimising disruption.

Options include:

• Basic replacement: Matches original specs.
• Upgraded units: Better thermal performance where compatible.
• Laminated glass: For added security if your frame supports it.

This approach is cost-effective compared to new windows and maintains your home’s appearance. Visit our main uPVC window repairs page for broader context.

How We Identify The Right Parts

Diagnosis starts with an on-site survey. We measure the unit’s exact dimensions, glass thickness, and spacer bar type.

We check frame rebates and compatibility to ensure a seamless fit.

Photos and notes confirm specifications, avoiding errors. Our experience with local installations helps identify non-standard sizes quickly.

Parts & Compatibility

Replacement sealed units must match your uPVC window’s dimensions and profile. We source from trusted suppliers for quality.

Common sizes fit most casement windows, but bespoke units handle variations.

Related Parts

Learn more about sealed units for double glazing, including types and specs.

Compatibility checks cover:

• Glass type (float, toughened).
• Gas fill (argon for insulation).
• Frame groove depth.

We avoid mismatches that could void warranties or cause leaks.

Pricing Guide

Costs for double glazed unit replacement depend on size, glass type, and accessibility.

Expect £150-£350 per unit for standard jobs, plus VAT. Larger or upgraded units increase this.

Factors include:

• Unit size (width x height).
• Glass specification (low-E adds 20-30%).
• Location (ground vs upper floor).

For full details, see our pricing page. A free quote follows inspection—no surprises.

FAQs

What causes a failed sealed unit?

Seals break down from UV exposure, pressure changes, or impacts, letting moisture in and creating mist.

How long does replacement take?

Typically 1-2 hours per unit, weather permitting. Multi-unit jobs may span a day.

Can I repair a misted unit instead?

No—internal mist requires full sealed unit replacement for a lasting fix.

Do you handle cracked units?

Yes, for safety, we replace cracked double glazed units promptly.

Is it compatible with older uPVC windows?

Most post-1990s frames work, but we check on-site.

What about energy ratings?

New units often exceed originals; we advise on upgrades.

When Repair May Not Be Suitable

Double glazed unit replacement isn’t ideal for all windows. We exclude sash windows, sliding windows, tilt and turn, or inward-opening types.

If the frame is rotten, warped, or the window is wooden, full replacement may be needed—we don’t cover those.

Severe structural damage or exclusions like glass clean-up mean we’ll advise alternatives honestly. Our liability insurance covers approved uPVC work only.

Call To Action

Ready for double glazed unit replacement? Contact us today for a survey.

Call 020 8138 0796 or email [email protected].

Local Sutton service—book now to fix your misted, blown, or cracked units efficiently.