Misted Double Glazing
Does your window have condensation inside the glass unit?
The condensation observed between the two panes of glass indicates that the sealed unit has become compromised. In addition to obstructing visibility and detracting from the aesthetic appeal, a misted or 'blown' double glazing unit is no longer functioning as intended. The failure of the seal has rendered the unit ineffective, as the air or gas-filled cavity that provides thermal insulation is no longer intact. As a result, the unit is unable to prevent the ingress of cold air, retain heat within the home, or allow solar energy to be absorbed, compromising both energy efficiency and comfort.
If your windows have misted, blown, or damaged glass, it does not mean that the entire window needs to be replaced. In many cases, you can simply replace the glazing itself, which is a far more cost-effective solution that avoids the disruption of full window replacement.
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Modern uPVC windows typically feature internal beading, while older models have external beading. Regardless of the style, the beading can be removed, allowing the misted or damaged glass to be replaced with a new, sealed unit. For externally beaded windows, depending on their age, the internal gaskets may also need to be replaced, as they can be brittle and may break apart during removal. However, these gaskets are a relatively inexpensive part and do not significantly impact the overall cost of the replacement.
Double glazing technology has advanced significantly in recent years, particularly in terms of both thermal and acoustic insulation. Older units often have thinner un-coated glass, air-filled cavities, and aluminium spacers, whereas modern A-rated units feature warm-edge spacer bars, gas-filled cavities, and glass coatings that improve heat retention and energy efficiency.
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If you are satisfied with the condition of your existing uPVC frames and do not require them to be replaced, upgrading your old glass to new A-rated units can substantially improve the thermal performance of your home, enhancing both comfort and energy efficiency at a fraction of the cost of complete window replacement.
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Interesting Fact
Windows with decorative lead patterns reduce the amount of external light entering a room by as much as 30% compared to clear glass. If you're seeking to maximise natural light in your space, switching from lead pattern glass to clear glass can significantly improve light transmission, creating a brighter, more inviting environment.
