To the best of my knowledge, gluvit is a sealant for the inside only. There are better products for the outside. Never heard of gluvit being used on wood, cant say it wont work, just always used other/ better products to seal wood. When I did my jon boat, on the outside I used a product called " leak stopper" availiable thru tractor supply and home depot. It is a clear roof sealant that is very tough. It can be painted over, in which I used rustoleum exterior enamal. Mine has been dragged over sand, rocks and other abrasive stuff and has held up very well. I used it on the inside as well, because the formed ribs on the bottom were actually worn thru, creating long cracks and yes they leaked like crazy!! The leak stopper is thicker than gluvit and would build up in the ribs in thickness to seal the cracks. Been about 5 years and still no leaks !! The gluvit is thin and gets into nooks and crannies to seal up tiny cracks and rivet heads. Most peoplebuse somevtype of epoxy or other wood sealer for the wood parts.