CompleteNewb wrote:
....

My vote is to sand and refinish the existing floor, but we may be getting
brand new hardwood, ...

I'd vote for option A and why B?

....

So, does anyone know why I have two sets of joists and subfloor, one on top
of the other? I've been to look at 3 old houses around town, and they just
have a floor, subfloor, and joists, and the joists are the same ones you see
in the basement. In my house, I have a floor, subfloor, joists, then more
floor, then more joists. The house was built in 1929, and is plaster
walls/ceilings, if that helps anything.

So, to sum up:

1) Why do I see diagonal subfloor pieces that stop and are replaced with
straight-running subfloor pieces upstairs? And does this add serious
complications to the idea of tearing up the top hardwood floor?

2) Why do I have a "double" floor, like a set of two complete floor
assemblies (subfloor and joists on top of subfloor and joists)?

3) Does anything described and seen in the pics mean that I'm in for a
world of hurt in terms of tearing up hardwood and putting in new?

No way to tell w/o being able to see the main portions of the structure,
namely the foundation, additions, if any, etc., etc., ...

All we have are some basically cosmetic views from the outside but
nothing from which to judge why it was deemed desirable to do what was
done. Certainly, it would be only reasonable to assume there was a
reason other than "just because".

One thought that is little more than conjecture given the age is that it
might have been thought desirable to lower a 10-ft or higher first floor
ceiling to cut down the heating load when the central heat was installed
and it was done by raising the floor instead of lowering the ceilings.

As for the flooring, hard to imagine there would be anything major that
would prevent pulling up what is there given the obvious solid
construction from what is shown.

That said, again, can't see why one would choose to do that instead of
refinishing what is there...

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