In article ,
WeeBob wrote:
The current floor is patchy quality old floorboards. My plan is to lay
plywood down on top of them. From what I read, I should nail or screw
the plywood to the existing floor... but also leave an expansion gap.

I'd say that unnecessary. Better to repair the existing flooring to an
adequate standard - well fixed and reasonably level. Sand the whole lot if
needed.

I'd not want to make the new floor even higher than needed.

--
*A conscience is what hurts when all your other parts feel so good *

Dave Plowman London SW
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