Is it possible to fix a subfloor from the crawlspace? We have dry rot under a shower in a bathroom that is tiled. The dry rot is about 3x3. This will prevent my from having to gut out all the tile which would then require basically a complete bathroom remodel since the tile can't be color matched.
First - Sorry to hear of this, have you found where the water is leaking from to cause this rot, as it really doesn't matter what you do to fix the results until you find the problem you will gat the same results.
I really don't think that the subfloor can be fixed from underneath, given the repair area is larger than the space typically found between floor joist, and tile will not support itself while you remove the rotten pieces.
When its all said and done there is usually more said than done
Thanks for the help. I should I mentioned that yes, I found the leak and its fixed (bad drain seal). I guessed that there would be a problem with what you mentioned re: tile support and beam distance. Thanks for confirming this.