repairing wet subfloor under ceramic tile
 

After 3 years in my new bathroom, a lot of water recently dripped on
the floor near the tub. It has not gone on for a long time, perhaps 1
-2 weeks. The caulking must have deteriorated a bit and water got
underneath one small tile 2 x4 inches, and partly under another tile,
4 x 12 inches so that the tiles (or part of a tile for the larger one)
are squishy - the grout is slightly cracked. I probably can pull up
the smallest tile - I am not sure if it is detached from the wet
plywood or whether the attachment is still good but the plywood is
just soft. I was thinking of taking up the one small tile, and letting
the area dry out - perhaps using blow drier or light bulb to do this.
If the wood gets hard I would cement it down and regrout. I am trying
to avoid lifting the second tile and wonder if the drying out will help
the adjacent tiles somewhat. ALso wondering if I need to put something
on the plywood before putting tile back to give it strength, if it
should not return to normal. it might be a real project to try to cut
out the small plywood subfloor area but perhaps there is no other way.
There is a second subfloor below this new 1/2 inch plywood.

thanks for any guidance. I have done ceramic tile over cement floors
but had a professional do this installation. I might have a few extra
tiles if one breaks during removal but I am trying not to make the
project into a big one

alan