Re: floor damage
If you haven't already tried a repair... Replacement?? If you have gaps you can replace with Airex composite or even exterior or marine grade plywood. Got to make feathered splices and epoxy the patches...
I am assuming you have some floor left and it is just soft...
Find some West systems epoxy and epoxy glass cloth. Mask off the surrounding side areas as epoxy is very difficult to clean up. After through cleaning with wire brush and vacuum of the floor, lay on a clear coat of epoxy. Lay down some strips of cloth and press them into the epoxy resin. Add more epoxy (you can add filler material to the epoxy if you desire at this point) to saturate the cloth. I used Keel weight cloth, but a hull weight would be OK. Double up the cloth in stress areas.
Then have a 1/2 or 3/8" plywood pattern already cut to match the outline of your floor. Easier to apply if you have the pattern cut into 2 or more pieces. Pre-drill a layout of screw holes in the pattern and lay down a sheet of plastic followed by your plywood pattern. Screw the pattern down to the existing deck with 1 1/4" drywall screws. The pattern acts as a clamp to hold the floor smooth and flat.
Let dry 24 hour and remove pattern and plastic. Clean up any squeeze out epoxy and your repaired deck is ready for carpet.
