The Problem – “Condensation”, “Misted”, “Cloudy” in the trade we say that the double glazed sealed unit has “Broken down” or “Failed”. This means that the perimeter edge seal has lost it’s integrity and that it is letting in moisture somewhere. The moisture itself is hard to spot at first, sometimes becoming only visible as the Sun or another heat source ’draws’ the moisture up. Typically the moisture will be drawn in as the atmospheric pressure changes, and it will build up eventually condensing into water inside the sealed unit. This can sometimes fill to look like a fish tank with several inches of water inside that cannot escape. Other cases re-activate the dormant desiccant chemicals inside the spacer bar, creating an acid which burns into the glass and when dried out will leave a white cloudy streak as in the pictures below.
The Cause – Other than natural atmospheric stresses, there are 3 main reasons for the breaking down of a sealed unit.
1. Poor manufacturing process with the use of inferior edge sealants. (non conforming components)
2. Incorrect frame drainage or a blockage in frame drainage.
3. Incorrect packing of the glass unit during installation or the use of incorrect packer products.
The Solution – The only answer is to replace the double glazed units. This will cause no alteration or disruption to the frame within they are located. However the replacement unit should be manufactured to Kitemarked standard and the unit replacement should always be carried out by a trained operative, in accordance with the Glass and Glazing Federation (GGF) Glazing Manual.
The CLEAR SOLUTION – Getty Glass only install premium double glazed sealed units, conforming with BS E 1279-2:2002, rigorously tested by the British Standards Institute (BSI) in order to offer Kitemark quality.
Many will claim that their products “conform” to various BS Standards, however only units that actually pass the rigorous testing of the British Standards Institute (BSI) carry the much coveted “Kitemark” status.