Adding to this I’m building a casting deck on my 16ft Starcraft aluminum. I want to waterproof the plywood I used before i put marine grade carpet on it. Just in case of leaks or heavy rain etc. In hindsight I should have used marine grade plywood but I was trying to save some money. Now the glue I have to use for the carpet will adhere to almost anything but some plastics and rubber. So using “liquid rubber” of any sort won’t work. Any suggestions would be appreciated.