I posted this pic quite some time ago showing rot around my toilet from
below.



I have now removed the toilet, a layer of tile, a layer of vinyl
flooring and the two layers of underlayment that were accociated with
the flooring.

I cut the rot out and now have one problem and that is supporting the
new subfloor I must install.



On the west side the tounge is available so that will not be a problem.
For the north, I plan to cut back to the floor joist or alternatively
cut even with the joist and add a sister to the floor joist to make
things easy for myself.
On the east, I will add a 2x4 to connect the floor joists and use that
for support.

That leaves the south... it is an outer wall and the floor joist is 6
inches in (beyond the floor I have cut out. I can only think of two
options (since there is plumbing in the way to make things worse....
(1) Add a hanger 6 inches in between the two joists, then put in a
crosser of some kind... or (2) screw some thick plywood to the bottom
of the existing subfloor and use that for support.

Any advice or other options?