John wrote the following:
Ok, I've removed my old floors, and used a laser level to get some
pretty accurate measurements of the floor height.

It seems that I have a single pair of joists which bow upwards. Thus,
they are 1/2" different in height than the joists on either side of
them (so 1/2" in about 5'). The joists at the other side are about
1/8" lower than my target height of the room, and thus, the floor
needs to be lowered in that one spot by about 3/8" of an inch. I
don't want to sand the floor board down, as this would weaken the
floor board to much in my opinion (the laminate flooring is running
parallel to these particular joists, so I can't count on them for
strength). My choices then are to raise the entire area by
1/4" (we're talking 400 square feet), or to rip off the floor boards
and plane down the joists.

The problem is that the floor (BCP) is nailed down with some pretty
old nails. My father lent me his 'Japanese nail-puller-outer' which
is an awesome tool BTW, but about half of the nail heads actually snap
off before I have the nail even 1/4" up.

So rather than pulling up 2 4x8 sheets, and all the nails involved,
I'd like to cut the board right beside one of the joists, attach a 2x4
to the joist, and put a replacement board that sits on the 2x4.
Hopefully that should be OK


My real issue is with the leveler though. I've never worked with the
stuff before and I'm getting myself a bit nervous about it.
Apparently, if you screw up with it, it's almost impossible to fix.
So, the plan there is to put some screws into the floor so the heads
are at the exact height I want to make the floor at each point. I
then use a small amount of the leveler, and a flat straight edge to
build tracks between the screws at the correct heights. I build a
grid using this method, and when the grid is done, I simply pour the
leveler in each square, and use the flat straight edge to level it.

I'm obviously going to do a trial before I do the final thing, but if
anyone has any advice on it, I'd love to hear it. In particular, I
have some nail holes in the BCP that go all the way through -- how do
I keep the leveler from leaking through those, or other cracks? If
one of my grids is not perfectly level, will that cause me problems
(I'm aiming for less than 1/8" drop per 5'?


(Note: On top of all of this, I'm getting some pros to come in and
give me estimates. If they charge an affordable price, and manage to
convince me they'll do the job right, I won't be doing any of this
anyway, but I'd still be interested in hearing any views/ideas for
interest sake)

John




Can you get to the joists from below (i.e. a first floor with a basement
below)?


--

Bill
In Hamptonburgh, NY
In the original Orange County. Est. 1683
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