When the roof was off, I noticed there were a few places the cavity wall
blown fibre had sunk (or never got there in the first place).

Google's not showing anything - can you get a bag of the fibres - or beads
(either would do)?

I can go by feel and stuff a bit more in when I fix the soffits later on...

Cheers,

Tim

--
Tim Watts Personal Blog: http://www.dionic.net/tim/

"A fanatic is one who can't change his mind and won't change the subject."