When you live in London , double glazing isn’t a luxury — it’s a necessity . From keeping the winter chill out to reducing the constant noise of city life , good-quality double glazing can make your home feel warmer , quieter , and more secure . But like anything in your home , even the best windows can develop problems over time .
The good news? Most double glazing issues are completely fixable — and often without the need for full window replacement . In this guide , we’ll walk you through the most common double glazing problems in London , why they happen , and how we fix them quickly and effectively .
Whether your windows are misting up , letting in drafts , refusing to close properly , or costing you money on heating bills , you’ll find clear , practical solutions right here .
Door Installation in London
Why Double Glazing Matters So Much in London
London is a city with character — and challenges . The mix of historic buildings and modern construction , unpredictable weather , and high noise levels means windows here work hard . Double glazing helps to:
- Keep homes warm in winter and cool in summer
- Reduce energy bills by improving insulation
- Block out street noise from traffic , trains , and busy nightlife
- Add an extra layer of security against break-ins
- Increase property value and comfort
But when double glazing fails , you feel the difference immediately — colder rooms , rising bills , annoying condensation , or even visible damage . Let’s explore the problems most London homeowners face .
Bifold Door Repair London
1 . Condensation Between the Panes (Misted Windows)
The problem:
One of the most common double glazing complaints is mist or condensation trapped inside the sealed unit . It looks like a foggy film between the panes that you just can’t wipe away — and it ruins the clear view your windows should give you .
Why it happens:
Double glazed windows are sealed to keep an insulating layer of gas (often argon) between the panes . Over time , seals can wear out or break down , especially with London’s damp climate . Once moisture gets in , it condenses inside the gap — causing that misty , cloudy appearance .
Why it matters:
- Reduced insulation → higher energy bills
- Ugly windows that ruin your view
- Possible long-term damage if left untreated
How we fix it:
We carefully remove the failed glass unit and replace it with a new , properly sealed one . Modern double glazing units are more durable , more energy-efficient , and often come with improved sealing technology — meaning you’re not likely to face the same issue again anytime soon .
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2 . Draughts and Cold Air Leaking In
The problem:
You feel a chilly draft even when your windows are shut tight . Not only is it uncomfortable , but it can also drive up heating costs and make your home less energy-efficient .
Why it happens:
- Worn or damaged window seals
- Loose or warped frames (common in older London homes)
- Poor installation from the start
- Gaps caused by building movement over time
Why it matters:
- Heat loss and higher energy bills
- Cold spots near windows
- Increased risk of damp and mould
How we fix it:
We start by identifying exactly where the draft is coming from . Often , simply replacing worn seals and re-aligning the frame is enough . In older installations , we may recommend refitting or upgrading the unit entirely . Either way , the goal is the same: a tight , weatherproof seal that keeps the cold out and the warmth in .
Front Door Repair London
3 . Windows That Are Hard to Open or Close
The problem:
Your windows are sticking , refusing to open , or won’t shut properly . This can be frustrating — and in some cases , a safety risk .
Why it happens:
- Frame expansion or contraction due to temperature changes
- Dirt and debris buildup in hinges or tracks
- Faulty handles or locking mechanisms
- Poor installation leading to misalignment
Why it matters:
- Security risks if windows don’t lock properly
- Ventilation issues in warmer months
- Risk of damage if forced open or closed
How we fix it:
We check the alignment of the window and adjust the hinges or frame as needed . If components like handles or locks are broken , we replace them with high-quality parts . And if the issue is due to poor installation , we realign the frame to ensure smooth operation .
Stable Door Repair in London
4 . Broken or Damaged Seals
The problem:
Even if you don’t see misting or feel drafts , damaged seals can silently reduce the effectiveness of your windows .
Why it happens:
- Age and weather exposure
- Building movement
- Incorrect installation
- Harsh cleaning chemicals that degrade the seal
Why it matters:
- Reduced energy efficiency
- Increased condensation risk
- Shortened window lifespan
How we fix it:
If the damage is minor , resealing the window may solve the problem . For more severe cases , replacing the glass unit with a new , factory-sealed unit ensures maximum insulation and longevity .
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5 . Leaking Windows and Water Ingress
The problem:
Water getting inside your home around the windows is a major red flag . It often appears as damp patches on walls , water pooling on sills , or even mould growth .
Why it happens:
- Failed seals or gaskets
- Blocked drainage channels
- Cracks in the frame or wall around the window
- Poor installation causing gaps
Why it matters:
- Serious risk of damp , mould , and structural damage
- Health risks from mould spores
- Reduced property value
How we fix it:
We identify the source of the leak and address it directly — whether that means resealing , replacing gaskets , clearing drainage , or repairing damaged frames . In most cases , proper sealing and drainage restoration stop water ingress completely .
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6 . Noise Reduction Not Working
The problem:
One reason people invest in double glazing is to block out London’s constant noise . If you can still hear buses , sirens , and neighbours clearly , something’s not right .
Why it happens:
- Seal failure allowing sound to leak through gaps
- Thin or poor-quality glass used in the unit
- Installation issues causing acoustic leaks
Why it matters:
- Reduced comfort and peace at home
- Interrupted sleep
- Lower property value in noisy areas
How we fix it:
We assess the glass and seals . If the issue is quality-related , upgrading to acoustic or laminated glass makes a huge difference . If the seals are to blame , resealing or refitting the unit will significantly improve soundproofing .
Double Glazing Door Repair London
7 . Locks and Handles That Don’t Work
The problem:
Faulty locks and handles are not just inconvenient — they’re a security risk .
Why it happens:
- Wear and tear over time
- Poor-quality materials in older installations
- Damage from forcing windows open or closed
- Misalignment affecting locking points
Why it matters:
- Compromised security
- Drafts due to incomplete closure
- Increased risk of break-ins
How we fix it:
We repair or replace faulty locks , handles , and hinges with modern , secure fittings . In some cases , upgrading the locking system can also improve insulation and reduce drafts .
Double glazing Lambeth
8 . Frames That Are Cracked , Warped , or Rotting
The problem:
Especially common in older properties across London , damaged frames can compromise your entire window system .
Why it happens:
- Age and weather exposure
- Poor maintenance
- Building movement
- Moisture infiltration over time
Why it matters:
- Structural instability
- Drafts , leaks , and condensation
- Reduced energy efficiency and lifespan
How we fix it:
We evaluate whether the frame can be repaired or if full replacement is more cost-effective . For timber frames , we remove rot , treat the wood , and reseal it . For uPVC or aluminium , we address warping or cracks and reinforce where needed .
Double Glazing London
9 . Blown Double Glazing Units
The problem:
A “blown” window happens when the seal fails and the insulating gas escapes . It usually shows as fogging , condensation , or visible gaps between panes .
Why it happens:
- Age-related wear
- Poor manufacturing quality
- Weather exposure
- Installation errors
Why it matters:
- Significant loss of insulation
- Increased energy bills
- Condensation issues
How we fix it:
The best solution is replacing the glass unit with a new , high-performance sealed unit . This not only restores insulation but also extends the window’s overall lifespan .
