I myself coated the deck of my boat with cheaper bedliner (rustoleum in a gallon can). I did this over CSM fiberglass as an extra precaution in case there were pinholes. This product goes on much thinner than the herculiner and has nowhere near the texture. When wet I believe it would be very slippery. It would probably require at least 4 coats to seal bare plywood and I don't know if I'd trust it for that. I put carpet over mine so I didn't care if it was slippery. Same goes for the Dupli-color bedliner that I have used for other stuff.