Households across the UK are being issued a critical warning as winter approaches: condensation forming inside your double-glazed windows is a serious red flag. This common issue is a clear indicator that the windows are likely not sealed or insulated correctly, a fault that becomes particularly costly during the festive season.
The Root Cause: Failed Seals and Saturated Desiccants
According to window experts EYG Windows, the problem almost always stems from a breakdown in the sealed unit. The seal that binds the two panes of glass together eventually degrades and cracks. Once this happens, moist air infiltrates the crucial air gap between the panes, leading to the visible condensation trapped inside.
Another frequent culprit is a fault with the window's 'spacer' bar. This component sits between the glass panes and is filled with a desiccant—a highly absorptive material designed to suck up any stray moisture. "If there is even the slightest imperfection in the seal, this desiccant can quickly become saturated," the experts explain. Once its capacity is maxed out, the excess moisture manifests as the frustrating foggy build-up homeowners see.
Consequences: More Than Just an Eyesore
The appearance of internal condensation is not merely annoying; it has direct financial and practical repercussions. It signifies that heat is escaping from your home, meaning the central heating you're paying for is effectively warming the outdoors. This flaw undermines the very purpose of double glazing, which is to provide thermal efficiency and reduce energy bills.
EYG Windows states plainly that significant moisture or water between the panes typically means the seal has completely failed. At this stage, the window units have often deteriorated past the point of functioning properly, offering little insulation value.
Repair or Replace? Weighing Your Options
For homeowners facing this issue, there is typically one main fix, but it comes with a choice. If the surrounding uPVC window frames are still in good condition, it may be possible to replace only the failed sealed units. Alternatively, a growing number of specialist companies offer repair services.
The repair process usually involves drilling a small hole into the spacer bar or glass pane. A fresh drying agent or desiccant is then injected to expel the trapped moisture, and an anti-fogging agent may be applied before the unit is resealed.
However, EYG Windows advises caution: "Resealing will solve the problem, but may not actually address the core issue." They urge homeowners to consider whether a repair's expected lifespan justifies the cost compared to a full replacement, especially as winter sets in and efficient windows become essential for keeping homes warm and energy bills manageable.
