@greg_harvey Yeah, sounds quite similar. We have secondary glazing in the living room and I think it's even legal, but it's a pain in the arse. They are huge (2+m by 1+m), no way to get them off. No access to the window and no way of opening them. So now can I see the rotting of the wood from behind the extra layer of glass. I like the French way better. I see quite a few illegal changes here. I can even see an air conditioning mounted so it's visible from the street. Must be highly illegal.