On Jan 8, 7:10*pm, wrote:
I am a novice DIYer who is attempting a second floor bathroom
renovation.I had to move my toilet about 5 feet so I could replace the
exising 30inch vanity wih a 42inch one.It was relatively easy to move
the toilet as I extended the 3inch ABS toilet drain paralell to the 10
inch floor joists.I removed the existing vinyl flooring, removed a
layer of 1/4 inch particle board, and had to cut out pieces of 1/2
inch plywood to move the toilet. Now I have to put the subfloor back
together again and install a toilet flange above a 90 degree 3 inch
ABS fitting.I want to put a solid subfloor down as I am installing a
larger soaker tub and will be laying granite tile.I am stumped/
overwhelmed by how I proceed next. I can't just pull up the existing
1/2 inch plywood and replace with it with--say-3/4 inch plywood
because some of the bathroom walls are sitting on the plywood.When I
cut part of the subfloor out for the drain I couldnt cut the plywood
down the middle of a joist because thats where the plywood was nailed.
So if I patch my holes with 1/2 inch plywood and put another 1/2 inch
on top, the subfloor will be weak where I patched my holes. The joints
of the patch will not be sitting on a joist.Whats the best way to
proceed?Also, is it better to lay my subfloor and then cut a hole
above the 90 degree bend to install my toilet flange, or extend a
piece of abs out of the 90 bend and cut my subfloor around it?
Thanks

You should have, and still could, remove the nails where the plywood
sits on the joists and put your seams where they belong. A Cat's Paw
is the tool for the job:

http://www.mikestools.com/Cats-Paws_1019.aspx

Another option is to sister a joist onto the side of the existing
joists to give youself a nailing surface.

http://www.hammerzone.com/archives/f...st1/sister.htm

Cutting the subfloor before installing it over the 90 is probably
easier since you'd need to measure it out anyway. Also less chance of
mis-measuring and cutting it wrong/damaging the 90.