In message , Aldrich
writes

The ceiling joists in our 1930's house are spaced at 12" (300mm). The loft
insulation rolls that I have seen in B&Q and Wickes are 1160mm wide. Should
I buy these and cut them down to 300mm, or are 300mm rolls available
elsewhere?

Buy the rolls that are about four feet wide, then cut to size, with an
ordinary hand saw, *before* unwrapping the rolls.

I was sceptical, but it works brilliantly :-)
--
Graeme, Scotland