I'm assuming you are replacing a wood floor. If that is the case this is what I did.
I ripped out the old floor without tearing it up so that I can use it as a template. I filled in all the old screw holes with epoxy so that the water does not rot out the bannisters.
I purchase fiberglass sheets to replace the wood floors. You can purchase them from Overton's. They are a lot lighter than wood and you can cut them with ordinary wood tools. I fasten them down with epoxy and stainless steel screws.
Instead of putting new carpeting down where I tear out the old one, I took the boat to a tuffliner dealer and he covered the floor with a gray liner. It looks so professional and sharp!
The fiberglass sheets at the time were actually chaeaper than marine plywood, but the difference was eaten up with the tuffliner method. It was more expensive than marine carpeting. However the tuffliner is a lot easier to take care off and it is not slippery at all when your feet are wet.
