"Ian Stirling" wrote in message
...
I have 12mm un-foil-backed plasterboard over a 2" gap, to a 50cm stone
wall.
It's a mite chilly, and I'd like to insulate it a bit.

Ripping out the lot, and replacing with plasterboard/celtoex/... is
obviously one option, but is "slightly" disruptive, and involves
a hell of a lot of work, as well as not inconsiderable expense.

Other ways.

I'd need to apply a vapour barrier to the inside - I'm currently thinking
of
something like Al foil wallpapered over the walls, and painted over.

I'd then like to drill holes between all the studwork, and simply blow
foam into the wall before replacing the plugs, making good, and putting
the foil on top.

Is there any means of DIYing the foam injection?
Other than buying several dozen bean-bags, and a funnel


Would the bean bags have flame retardant beans in them? :-))

The proper way would be to strip the lot off and place your vapour barrier
against the stone. Then strap the wall with timber studs before filling the
gaps between them with fibre wool. Clad the whole lot over with tapered
edge 12mm plasterboard, or foil backed stuff if you wish, before sealing the
joints and making good the decor'.

Or you could get the new flame retardant paper insulation stuff and a
machine to blow it into the holes you make all over the plasterboard.

Going to the expense now will surely save you having to make other bigger
changes in the near future. Making good the insulation is a job that needs
doing properly from the start, and not bodging it up as you go along.