I have a bathroom where, due to poor calking, the floor has rotted. The floor is tile and still looks fine, but when I go in the basement and look at the floor above the floor is rotted completely thru and I can see the bottom of the tile. The amount of rot is about 5x5 inches.
What I want to do, for now, is use some filler material and fill in the rotted wood. Then take a piece of plywood and toenail it into the floor joists, or use a couple of blocks to screw to the floor joists.
Any recommendations on what to use for filler?