I've decided to abandon the loft leg idea, leave the wool insulation between the joists and use solid insulation over it instead then put the boards on top of that.
hoping i won't have to screw anything down either, maybe just a bit of glue on the insulation boards to the joists?
This is what I did in my current house, the loft board move a little but I am only using it for storage.
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And the cobwebs eughhhh. Run!
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