Dave Liquorice wrote:
On Tue, 20 May 2008 07:11:46 -0700 (PDT), RobertL wrote:

One simple solution is to use some wooden 4"x2" props with carpenter's
wedges to adjust the height. But I am worried about creating a damp-
conducting path up to the joists even if I stand the base on damp
proofing membrane.

The normal solution would ne to build a sleeper wall under the joists and
pack up to the underside of the joists with a DPC (a bit of slate is
strong in compression). Props will work but you'll have to think of a way
of stopping the wedges working loose over time and possibly some means of
spreading the load on the soil so they don't sink in.


How much does this piano weigh? A Yamaha grand is only 250kgs. Ten bags
of sand isn't going to do much to any floor. People are quite heavy
these days as well.