Fogged Double Glazing Replacement Dublin & Wicklow

Condensation inside double glazing occurs when the perimeter seal of the sealed glass unit fails, allowing moisture to enter the space between the panes. Normally, this cavity is filled with dry air or argon gas, which provides insulation. Once the seal breaks, water vapour from the air seeps in and condenses on the cooler inner surfaces — leading to fogging, misting, or visible water droplets inside the glass. This is a sign that the window is no longer airtight or energy-efficient. The issue can’t be repaired from the outside, as the moisture is trapped within the unit itself. The only lasting solution is a replacement double-glazed unit, made to the exact size and specification of your existing frame. At P Fahy Glazing Ltd, we provide fast, professional double glazing replacement across Dublin and Wicklow, restoring your window’s insulation and clarity. 

Both phrases — condensation inside double glazing and condensation between double glazing panes — describe the same issue: a failed seal that allows moisture to enter the sealed cavity. However, condensation “inside” refers to what you see within the glass itself, while condensation “between” highlights that it’s trapped in the narrow air gap separating the two panes. In either case, the moisture cannot be wiped away or cleaned from inside or outside the window. The insulating gas has escaped, reducing the unit’s ability to retain heat and block noise. Replacement is the only effective fix. Our team at P Fahy Glazing Ltd carries out misted double glazing replacements throughout Dublin and Wicklow, fitting new sealed units that restore both performance and visibility without disturbing your existing frames.

Once condensation forms between the panes, repairing misted double glazing is unfortunately not possible. The unit relies on an airtight seal to trap insulating gas and prevent moisture. Some companies offer “defogging” services that involve drilling small holes to release moisture, but these are temporary, cosmetic fixes that don’t restore the lost insulation or clarity. In time, the window will mist up again. The only permanent and effective solution is a complete double glazing replacement, where the failed glass unit is replaced with a new, fully sealed one. At P Fahy Glazing Ltd, we provide professional replacements across Dublin and Wicklow — measured to fit perfectly within your current uPVC, timber, or aluminium frames, restoring full energy performance and a clear view.

Many Irish homeowners are noticing misted double glazing more frequently because a large number of homes were fitted with double glazing during the building boom of the early 2000s. Those sealed units are now reaching 15–25 years old — the typical lifespan of perimeter seals. Earlier units were not built to the same standards as today’s A-rated glazing. Some builders also used cheaper, short-lived seals and spacers to save costs. Combined with Ireland’s damp climate, this leads to widespread condensation inside double glazing as these seals begin to fail. Modern replacements are far more durable, using advanced gas fills, warm-edge spacers, and stronger sealants. Our team at P Fahy Glazing Ltd replaces older misted glass with today’s energy-efficient double glazing, helping homes across Dublin and Wicklow enjoy clearer, warmer, longer-lasting windows.

If the moisture can be wiped away, it’s surface condensation caused by humidity or temperature differences in the room. If you can’t reach the condensation from either side, it’s trapped between the panes — a clear sign of a failed seal. You might also notice streaks, fog patches, or marks that change with the weather. This type of condensation inside double glazing won’t go away on its own and usually worsens over time. Once the insulating gas has escaped, the glass loses efficiency, clarity, and soundproofing. The solution is to replace the sealed glass unit. We offer quick, clean misted double glazing replacement services in Dublin and Wicklow, ensuring each unit is custom-made for your window and fitted with minimal disruption.

While misted double glazing doesn’t pose a health risk itself, prolonged condensation between panes can lead to secondary issues. Trapped moisture can slowly migrate towards the frame edges, encouraging mould growth or rot in timber windows and corrosion in metal ones. It can also contribute to draughts and cold spots around the window, making rooms less comfortable and more expensive to heat. Additionally, poor visibility through fogged glass can be a safety concern in stairwells or doors. Replacing the failed unit with a modern, sealed double-glazed pane eliminates these problems permanently. At P Fahy Glazing Ltd, we fit high-quality double glazing replacements designed for long-term insulation and clear visibility across homes in Dublin and Wicklow.

Yes — when the seal fails, the gas between the panes escapes, and the insulating barrier disappears. This allows warm air to escape and cold air to enter, reducing your window’s ability to retain heat. Over time, this can make rooms noticeably cooler and drive up heating costs. Many homeowners don’t realise how much warmth is lost through failed glass units until they’re replaced. A new A-rated double glazing replacement immediately improves insulation and comfort. Our team installs energy-efficient Low-E glass across Dublin and Wicklow, restoring warmth while keeping the existing window frames intact. The result is clearer glass, better comfort, and measurable energy savings.

At P Fahy Glazing Ltd, most misted double glazing replacements are completed within a few days from your free site visit. We begin by taking precise measurements, then have the new sealed glass unit manufactured to your exact specifications. Once it’s ready, installation typically takes less than half an hour per window. Our glaziers remove the failed unit, clean the frame, fit the new glass, and reseal everything neatly — with no mess or damage to surrounding plaster or paintwork. For urgent replacements or broken windows, we also offer an emergency board-up service across Dublin and Wicklow to keep your property secure while your new unit is being prepared.

Intermittent condensation between double glazing often means the seal is starting to deteriorate, but not yet completely failed. During damp or cold weather, moisture is drawn into the cavity and condenses on the inner surfaces. When conditions change, the fog may temporarily clear, giving the illusion that the problem has resolved — but the seal damage remains. Over time, the moisture will accumulate permanently. If you’ve noticed condensation coming and going, it’s best to arrange an inspection before full failure occurs. Our local glaziers in Dublin and Wicklow can assess and replace your failing double glazing quickly and professionally.

Unfortunately, DIY repair isn’t possible once condensation forms between panes. The seal is part of a precisely engineered system that requires specialist manufacturing. Attempting to drill holes or heat the glass may worsen the problem and damage the frame. The most effective solution is a professional double glazing replacement, which involves removing the old unit and fitting a new sealed glass pane made to exact dimensions. At P Fahy Glazing Ltd, we handle the entire process — from free inspection and measurement to clean installation — restoring your window’s performance and appearance without replacing the entire frame.

Yes. If moisture remains trapped inside double glazing for months or years, it can migrate to the edges and cause deterioration around the frame. Timber can swell, soften, or rot, and even uPVC frames can develop discolouration or mould at the seals. Replacing the failed glass promptly prevents this damage and protects your existing frames. Because we only replace the sealed glass unit, not the entire window, our process is clean, fast, and cost-effective. Homeowners across Dublin and Wicklow rely on us to extend the lifespan of their windows while eliminating fogging and condensation issues. correct specification — whether toughened, laminated, or energy-efficient glass — and installed with precision for long-lasting performance and safety.

Yes — modern A-rated double glazing is designed with vastly improved materials. New units use dual-layer seals, warm-edge spacer bars, and argon gas fills, all of which resist moisture penetration far better than older designs. The result is a longer lifespan with zero condensation inside the glass. Replacing failed or misted windows with modern glass doesn’t just restore visibility — it enhances comfort, energy efficiency, and long-term reliability. Our high-quality double glazing replacements, fitted across Dublin and Wicklow, are built to meet today’s energy standards and last significantly longer than early 2000s installations.

Absolutely. When you replace a misted or fogged double-glazed unit, it’s the ideal time to upgrade to Low-E (low-emissivity) energy-efficient glass. These modern units include an invisible coating that reflects heat back into the room while allowing sunlight to pass through. Combined with argon gas fill and warm-edge spacers, Low-E glass dramatically improves insulation and comfort. You’ll notice warmer rooms, reduced condensation, and potential savings on heating bills. We fit A-rated Low-E double glazing replacements throughout Dublin and Wicklow, ensuring every new unit performs far better than the glass it replaces. See how Low-E glass can improve home comfort here.

Costs depend on the size, glass type, and accessibility of your window. Replacing just the glass is significantly cheaper than installing new frames. At P Fahy Glazing Ltd, we offer free call-outs and no-obligation quotes so you know the price upfront. Whether you need one fogged window replaced or a full house of misted units, our pricing is transparent and competitive. We provide high-quality double glazing replacements across Dublin and Wicklow, measured precisely and fitted cleanly — ensuring long-term clarity, warmth, and value for money.

Older double-glazed units last around 15 to 20 years before the seals begin to fail. Factors such as manufacturing quality, sunlight exposure, and frame movement affect lifespan. Early 2000s units, now common across Dublin and Wicklow, are reaching this age — which explains the recent surge in condensation between double glazing panes. Modern replacement glass lasts much longer thanks to improved technology. When we install new A-rated units, homeowners can expect decades of reliable performance before any seal wear appears.

No — condensation forming on the outer surface of new double glazing is actually a good sign. It shows that the glass is insulating so well that the outer pane stays cool while the inner pane retains heat. This harmless external moisture usually appears early in the morning and evaporates as the temperature rises. It’s completely different from condensation inside double glazing, which indicates seal failure. If you’re unsure, we can inspect your windows anywhere in Dublin or Wicklow and confirm whether external condensation is normal or internal fogging that needs attention. For more information see Pilkington.

You can replace individual misted or fogged windows without affecting the others. We frequently replace one or two failed units while leaving the rest of the glazing untouched. Each new glass unit is made to the exact dimensions of your frame for a perfect fit. However, if several windows are misting at once, it can be more efficient to replace them together for consistent appearance and performance. We offer flexible double glazing replacement services across Dublin and Wicklow, so you can replace as few or as many units as needed.

No — if you can wipe away the condensation from the inside of the glass, your double glazing does not need to be replaced. This type of moisture sits on the room-side surface of the window and is caused by indoor humidity, poor ventilation, or temperature differences, not a failed seal.

It occurs when warm, moist air from cooking, showers, or drying clothes comes into contact with colder glass and condenses. The primary solution is to improve air circulation — for example, by opening trickle vents, using an extractor fan, or slightly raising the room temperature to help balance moisture levels.

Upgrading to modern energy-efficient glass can also help reduce this type of condensation in some cases, as the inner pane typically stays warmer, making surface condensation less likely. However, ventilation and moisture control remain the key factors.

Condensation that can be wiped away is different from condensation trapped between double-glazing panes, which indicates a seal failure within the glass unit. If moisture appears between the panes and cannot be touched, the unit will need to be replaced.

Our team at P Fahy Glazing Ltd can assess whether your condensation issue is surface-related or caused by failed double glazing, and provide clear, professional advice anywhere in Dublin or Wicklow.

Yes — every double glazing replacement we install comes with a 10-year performance guarantee covering seal failure or condensation caused by manufacturing faults. This ensures long-term clarity and insulation for your windows. The guarantee does not cover accidental damage or breakage, but all materials and workmanship are backed by our reputation for quality and reliability. Homeowners across Dublin and Wicklow trust P Fahy Glazing Ltd to replace fogged, misted, or condensation-damaged glass units quickly and cleanly — with results built to last for years.