On 3/8/2010 7:10 AM, Stormin Mormon wrote:
I've heard to use tongue and groove plywood. Because the
seams between the two boards interlock, and you have less
creaking and unstable feeling when walking across the floor.

Actually, I had T&G plywood in my
previous house circa 1971 and I can tell
you the squeaking was just as bad or
worse than anything I have seen. I
think, and that all it is, think, that
the tongue actually squeaks rubbing in
the groove. I re-nailed many places and
used those break off screws that go
through the carpeting to quiet things
down. When replacing the carpeting, you
know, for the potential new owners, I
put in a bunch of screws. I figured
that I would still be living there for a
time and I actually did for about 6
months until it was sold.