I am about to but new upvc windows fitted with K glass double glazing. I was amazed by the fact that 3 out of the 4 the vendors I contacted asked me if I wanted to opt for K glass. As far as I know K glass has to be the only option in view of the new building regulations. Apparently, there are still plenty of retailers trying to sell non K glass units. Does anyone know a foolproof way of identifying K-glass without shelling 60 quids of so for some specialized equipment?
Thank,
Alex.