Last year when we were in Fort Lauderdale there were three Super Maramus that had this repair done, one after another. One guy went from one boat to another. By the time he got to ours (#3) he had it down pretty pat. Ours was really very rotten, one of those repairs we postponed from the previous year yard time as not "urgent."
The decomposed plywood was cut out and replaced with divinylcell structural foam, glassed on each side. The glass "shelf" that supported the plywood was kept and used as the bottom support of the new locker bottom. In the absence of structural foam, plywood could certainly be a satisfactory solution if sealed on both sides. Either solution done well should last the life of the boat.
For reasons that escape me, Amel installed the plywood bow locker floors bare on the bottom. If yours are not rotten now, they will be--at some point. Even if rot from the humidity in the anchor locker was not an issue, glassing one side of a panel is mechanically a very weak structure. Kind of like building a bridge with an I-beam that is missing the bottom plate!
If you have the anchor locker opened up, you should also be aware that the upper part, of the forward side, of the bulkhead that makes the back of the anchor locker was also unfinished and suffers rot because of it. Since we had everything open, we ground off the compromised wood there too, and replaced it with a couple layers of glass.
Cape Eleuthera, Eleuthera Is., Bahamas
---In amelyachtowners@..., <no_reply@...> wrote :
As I was re-wiring my nav lights from the port bow locker (empty) I heard a crack. The top layer of the marine plywood floor separated from the rest and the floor is bowed but not cracked through. I checked it from top and bottom and it doesnt seem rotten. In case you’re wondering I weigh 200 lbs so it wasnt overloaded (ha). I know of at least one other SM that had this happen. Im in San Blas so an Amel fix in Martinique is out of the question. I will need to do this myself in Shelter Bay. Would love some ideas.