Good evening buildingregstrackworld!
I’ve been getting a few quotes to fix up the flat roofed bits of our house. As part of this I want some proper insulation on the utility room roof, which currently has a worthless amount in the ceiling space, a long way off any vaguely recent regulations.
As I understood it, if we’re adding any insulation at all then it has to be to the current standard, ie. a u-value of 0.18 or better. So why have all the companies I’ve asked so far just wanted to put a random – and insufficient – thickness on? I think it has to be 140mm, but the quotes so far have been for 90, 70 or 50(!) mm.
Are the regs not as strict as I thought? Are they just making it up assuming most people will not know or care? Or do they know something I don’t that makes a thinner layer okay?