Yesterday I started removing the old cabin floor which started to disintegrate. I could not find any prominent rot so I concluded that the plywood simply could not survive the strain of constant wear and tear. This is because the underlying structure did not adequately support the cabin floor.
Above: The old cabin floor, looking into the bilge.
Below: The bilge after the cabin floor was removed. Note all the dust and gunk that accumulated below the floor.
Below: Some plywood that was removed. The large piece is from the starboard bunk and is still in good condition.
Below: The old engine bay, with the position of the old engine mountings still visible.
I hope to sand the bilge and floor this week after which I will give it 2 to 3 coats of hard-wearing enamel paint. Additionally I plan to build up the supporting structure with plywood and epoxy after which I will install 18mm marine ply for the new cabin floor.