wrote:

Looking to board my attic for storage; it has some scrappy Rockwool
and joists are 4"x2". I was wondering whether to plant 2"x2" timbers
on joists to allow for greater depth of Rockwool, or maybe the
chipboard would provide enough extra insulation? Another thought -
better grade insulation material in place of Rockwool but in the same
4" space? Any ideas welcomed.

If you are looking at better grade insulation, you could simply lay a
rigid foam board insulation over the joists and then screw the flooring
down through it. No need for extra battens etc, and no additional weight.


--
Cheers,

John.

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