On Tue, 28 Aug 2012 13:11:50 +0100, David WE Roberts wrote:

I suppose I could interrupt the run at two joists and have a small
panel of chipboard to lift - will have a look at that.

That is what I would do, gives you a nice big opening to work through.
The hole saw linked to is only 110mm dia, you try getting a hand through
110mm dia hole to holed a wire or wires in place without considerably
obscuring what you are trying to work on.

Personally I'd not want anything sticking up, like a blanking plate
over a drylining box.

Not sure I completely follow this bit.

I envisaged the drylining box mounted into the floor. The blanking plate
would then project above floor level.


Having experienced problems accessing wiring buried under loft boarding in
this house, when helping my son board his loft using T&G chipboard "loft
boards" I did cut three holes in the board above tricky bits of wiring. I
then simply screwed a bit of steel sheet over each hole. Nothing fancy other
than rebating one hole so that the steel plate sat flush with the boards as
it was in the way of the slide down loft ladder. The other two were just in
general storage area so I just laid the plate on top with about an inch
overlap and a screw at each corner. I did countersink the screw holes which
my son considered to be OTT, but that's me!

Incidentally! What are those "loft boards" made of? I had sparks coming of
the router cutter when I cut the rebate!

Mike