Why does the council want to look at my loft insulation after roofing work?

[SilverHawk]

I can find no reason on the Councils own web site.
They would have to come into the house and not peer in from any scaffolding as the roof is boarded.

Building regs?

Checking it's the right thickness?

Building control to ensure building regs have been complied with?

If you've recovered your roof (more than 25%, I think) you were obliged to upgrade your insulation to current building regs standards (250mm equiv)

I had been told that like for like work needed no Building regs. I am no changing a thing.

X post! FunnyBird that's probably it as it's >25%. Thank you.

Can anyone explain 250mm or equivalent? The loft is full of junk, does that count

Well I'm not up to date, so it might be more than 250mm by now.
What I mean by 'or equivalent' is it would be 250mm of fibreglass quilt. But high performance insulation board or whatever could be thinner.