To us, external condensation on energy efficient windows is part and parcel with the industry. There are glasses from Pilkingtons and Saint-Gobain that combat this, but for many installers, there have been years and years worth of installations in which the windows they installed in homes around the UK will have a morning or two of external condensation. Specifically around this time of year, and the Spring.

Banned from site…nearly

For home owners though, it can be an unexpected, and sometimes unwelcome surprise. So much so that in one case, the customer almost refused to let this installation company back on site to complete a project they had already started:

Started a large installation last week… lads arrived on site yesterday and the client refused to let them in as he had external condensation and said our product was not fit for purpose! We showed him our ” external condensation” leaflet , but he thought we were trying to pull the wool. Any way, after 2 hours he phoned and said we could carry on as he had done his own research!

This was a private message sent to me from an installation company. It demonstrates perfectly that with a phenomenon like this, coupled with an industry reputation that is less than perfect, home owners can easily think we’re trying to mislead them as to the cause of the condensation.


I’ve said it before and I’ll say it once again, education on this topic is vital. It was only last week that we had a customer of our own come into the showroom to ask why they had external condensation on their windows this morning.

After a few minutes of explaining why it happens and the science behind it, they left more than happy. I think for some home owners there is an initial panic, with the thought that there must be some drastic problem causing it. Every home owner I have spoken to about it is satisfied with the reasoning, and fully understand that is isn’t a problem in the conventional sense of the word.

Should these new anti-condensation glass products from Pilkingtons and Saint-Gobain become the norm? Probably, it would save a lot of us time spent on the phone. But the reality is that it won’t, and will be left as an optional upgrade.

So instead, I fully believe that there should be a larger scale awareness push from the industry to home owners to explain why they get external condensation, the science behind it (mainly so that they don’t think we’re lying!) and that in fact it is physical proof that their brand new energy efficient windows are doing their job.

I will start to look at putting extra content on DGB Consumer over the next few weeks to try and do my bit, and you’re all more than welcome to use that content for your own sites or to show customers should they query you about their external condensation issue. But we should all be doing more to communicate this temporary effect to home owners and make it crystal clear that it isn’t a problem or a fault, but something that occurs naturally.

To get daily updates from DGB sent to your inbox, enter your email address in the space below to subscribe:

[wysija_form id=”1″]