Double glazing is now a standard feature in all modern window systems, having supplanted single glazed windows since the 1960s. In the early days the product had its faults in terms of misting-up with condensation. Since then, major improvements in their construction and installation have eliminated these problems. The industry is now dominated by large manufacturers who supply products which are continuously audited for quality assurance, ensuring they comply with, and regularly exceed, British Standards.
The extraordinary rise in heating costs over the past decade has forced owners of historic buildings to look at reducing running costs. Secondary glazing has had some appeal, but it’s been limited by aesthetic drawbacks. As an alternative, a slim double glazed sealed unit was developed, but not without its own reliability issues. The Glass and Glazing Federation (GGF), the industry body responsible for the manufacture of double glazing in the UK, has issued some stern warnings about the quality of slim (narrow cavity) units with reduced sightlines. In essence, the depth of sealant on the edge of double glazing is critical to both its longevity and performance.
It is the GGF’s position that only double glazed units which have met and passed the stringent British Standards tests (known as EN1279 parts 2 and 3) are suitable to be placed on the UK market. There are numerous suppliers currently offering products that do not comply with GGF rules, including the following companies:
Fortunately, development has continued and there is now 3 suppliers in Britain complying fully with GGF requirements:
|The Original Glass Company||Histoglass||Slimlite||Timbalite|
|Compliant with parts 1-6 of BS EN 1279|
|Available with a 10mm unit|
|Available with 4mm Krypton gas cavity|
|Able to achieve U-values of 1.1 W/m2k|
|5 year product guarantee|
|Compliant with Document L of Building Regulations|
Giving project architects the smoothest time possible from the time of planning to final installation, we develop Heritage units that help you overcome even the most difficult expectations.More About Glass Units for Architects
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