"John Rumm" wrote in message
...
Keith Dunbar wrote:

Right. Sounds promising, and not too expensive - given that I would only
need to put the PIR foam boards where I want to have flooring (I'm going
to put 8' x 4' sheets of chipboard on 2" x 1" timbers between rafters for
the bulk of my storage).

With rafters being the sloping bits, I am having trouble visualising
this...


You must forgive my ignorance of the names of all the funny bits of roofs
.....
(maximise screen to view this best)

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| oooooooooo | | ooooooooo |
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There is just about room for a 4' width of chipboard at "ooooooooo"

Where would I be best (i.e. cheapest) going to for this PIR board? How
strong is it?
Can one stand on it? I would need lots of quite long screws to fix the
flooring to the joists.
Is there any reason why I should need to. Could I create a sort of raft of
flooring above the PIR?

Thanks so much for your help.

Keith