Ian French wrote:


Am I on the right track here? Any ideas or information would be most
welcome before I do it and find that our beloved piano has crashed through
the floor!

Thanks

Steve
Hi,

You could of course "Test" your floor before engaging in all this work,
without any Pianos being involved.

I think that there is definitely some strengthening to be done.

You get 7 adult men, who will weigh about 14 stone (75Kg each, 525Kg total),
to stand where the heavier piano is to be placed, and 3 adult men (total
225Kg) to stand where the lighter piano is to stand.

Our original plan to test the floor was to fill three 200 litre water
butts to full in the strategic positions and then us and friends to
jump up and down to see if the floor failed! This plan fell through,
sorry!, once I started taking the floor up and found that it, most
probably, would have failed catastrophically due to the poor state that
the floor was in and also a lot of past bodges that needed attention.

If the floor survives this test without any groaning, then you can get them
to jump up and down to give the floor a shock load.

If you are worried about the point loading then maybe you need to fit steel
plates to the floor to spread the load.

The point loading is a worry but with the proper cups under the castors
and stiffened joists this does not seem to be so much of a worry as
absolute strength.

Steve