On Sun, 16 Aug 2009 13:17:50 -0700 (PDT), NT wrote:

On Aug 16, 12:13*pm, PeterC wrote:
On Sat, 15 Aug 2009 13:27:56 -0700 (PDT), NT wrote:
I'm trying to get them flush but that in itself is cracking the board. I
might have a go at putting in a flush countersink and propping the board,
so that the only starin is the weight.

If you mean countersinking and predrilling each hole, in extremis that
does help, and sounds like it may be worth it for you.

Yes. A bit slow, but I'd need fewer screws anyway, as they should be better
at holding. Doing it this way, I can push the board upwards with one hand
whilst running in the screw.

It sounds like youre out of other faster options. Any fixing that
breaks the board up will make things worse rather than better.

There is another way, but probably not warranted in your case. Prop
the ceiling up using timber uprights and sheets of whatever, then lift
some floorboards above and pour a thin plaster mix on.

NT

Hadn't thought of that - thanks.
It's actually a case of lifting the insulation, as this is to the loft.
--
Peter.
The head of a pin will hold more angels if
it's been flattened with an angel-grinder.