Originally Posted by spaghettiroad
Apparently the water tank is new so I'm guessing that was the issue. Nonetheless I will check all that was recommended. What kind of sealer to seal the tin on the underside ? As well could I not use pl400 construction adhesive on the wooden patch ?
There are as many ways to repair a floor as handy folks on this forum. I'd recommend searches, perhaps, using the google portion of the search feature above.
FWIW, I cut out an area just about the size of the rear floor that you face, I suspect. One area was so rotten that I broke it out with a hammer and had a nice view of my driveway concrete below.
I was determined to cut back the rotted floor until only good, solid floor was present. I also cut out in the pieces square allowing for a tighter, truer fitment of the replacement.
I then took a 1/4" treated plywood board and screwed it to the floor from below. I did spray seal the edges of that board with polyurethane. This merely acted as a construction "basket" to hold the floor repair above in place.
Again, this acted as a temporary support for the replacement flooring piece which I installed from above, screwed from below. I used gorilla glue and coated the edges of the repair pieces and fit them in tightly. I also flowed gorilla glue into the seams and it seeped down and filled the seems. Repeated until the seams were virtually solid gorilla glue. Frankly, it was incredibly strong and only took about 3 or 4 ounces of gorilla glue to accomplish the task.
Honestly, it is as good as new, if not better than new.
Finding and repair the source of the leak is essential, of course, so to stop any future damage.