Often a question asked by a waiter when ordering water in a foreign restaurant but some customers are asking the same question here in the UK, concerning double glazed sealed units.
When sealed units were simple (air filled) the only issue was the amount of water vapour trapped between the two sheets of glass, when the sealed unit was manufactured. Silica gel crystals provided a simple solution, as they would suck out any moisture so trapped for the life of the sealed units.
The only reason sealed units get misty between the sheets of glass is because the perimeter seal has failed, allowing more air and moisture to enter the sealed unit (more than the silica gel crystals can cope with) so moisture forms on the inside face of the glass. Sometimes (like the above pictures shows) the crystals fall out of the spacer bar!
With modern sealed units gas is often used but how do you tell if your new windows have got the argon or krypton gas that you have bought?
Well it is virtually impossible for retail customers to establish, however there are spark guns that can fire electrodes that measure the resistance of the gas, however these are expensive and not entirely accurate. frankly the best solution is to go to a reputable company. Any decent company just doesn’t cheat its customers, its part of the process, it get done, and if accredited by a third party, BSI, BBA etc then they check the records to show the purchases of gas.
I guess however that if you choose to pay the cheapest price for double glazing, then it is an obvious place for a company to cut back on, sell it a gas filled and dont bother doing it!
Moral of the story, be happy that the specification you get shown (and agree to), gets written into the contract you sign for. Make sure you know the company has the third party accreditations it claims, so that you have confidence you should get what you expect, or just buy the cheapest of cheap but don’t be surprised that its not quiet what you thought you had ordered!
Beware, triple glazing has many benefits but one significant drawback is that e
The concept of gas between panes of glass is that the inert gases used are dense and therefore are less conductive of heat. This slows heat loss from your home through your windows, making them more efficient than standard double glazing. In fact Advanced Group Scotland combine this with low E glass ,carbon fibre spacer bars and foamed filled profile frames to produce the ultimate u-value window of approximately 0.8.
In terms of proving the gas is inside the unit, this can be more tricky! Some manufacturers of glass units will run their production within a gas filled chamber so that the unit captures the inert gases before it is sealed. We however prefer to seal the unit completing then fill each unit individually by injecting the gas through the seal. This enables us to have complete control over the amount of gas that is captured in the units to ensure that all oxygenated air has been expelled. This results in a small hole in the spacer bar which we then “plug”, this is visible to the experienced eye therefore confirms the presence of the gas.