Many of you will have woken up to condensation on your windows Monday morning. Not on the inside of the window of course, but out on the outside. Specifically on the outside of the outer pane. This affect is a well known phenomenon now among the glazing community. We all know how big an “issue” this has become over recent years. But a quick Google Trends search puts that into perspective.
Rapid rise after WERs
Just take a look at this graph Google Trends spits out when you put in the term “window condensation”:
The search term is a bit general, as window condensation could also be on the inside of the window, but when you consider the timing of when Window Energy Ratings were introduced and when they became law, this graph starts to make a lot of sense.
There is an increase in activity around the 2008 mark, as they start to become more well known and used. Then there is a marked increase around the 2010 mark when in that year WERs became a regulation, greatly increasing their scope and influence in the window industry.
But as the current crop of energy efficient windows became more and more widely installed, a problem with external condensation on some mornings started to become a bit more regular. The more energy efficient windows were installed, the wider this phenomenon became.
Of course we know this isn’t a problem in the common sense of work. It is physical proof that the windows are indeed doing their job. For most home owners, a quick explanation as to why external condensation occurs is enough, because by the time it has been explained, the condensation is starting to disappear from their windows.
So there are two things as an industry we can do. Firstly, we can explain this effect to customers during the sales process. In my experience, most have been happy to have been told. If they know it’s coming, they already know it’s not a fault with the product. Alternatively, both our major UK glass companies, Pilkington and Saint-Gobain both have anti-condensation glasses designed to combat this weather-related effect during the Spring and Autumn months.
One thing is clear though, external window condensation is going to be here as long as energy efficient windows are, so we all might as well get used to it.
We agree, it’s all about the explanation – heading off any questions before they arise.
Our robot, Mark II, has written a blog post with this in mind, and installers can download a handy sheet that helps explain condensation to customers if they visit http://www.liniar.co.uk/blog/condensation/.
DGB
If I may be pedantic on this one , the phenomenon has nothing to do with WERs , and WERs are not a regulation.
The phenomenon is purely down to insulation , the buildings regs insist on insulation u-values of 1.6 or better , however the WER compliance method actually allows u-values of up to 1.9 , so giving WER any credit for improved insulation is misleading , if the WERs were not around windows would need to be better insulated.