Re: Fiberglassing over marine grade plywood help
That wont solve your original problem of the sogy floor. The floor isn't just fiberglass, even though fiberglass is strong it would have to be about 4" thick for a 4' wide deck not to flex. the floor/deck on your boat is most likely a wood floor that has been fiberglassed over. it's a common boat building practice, but when moisture finds it's way through the fiberglass and it will, it rots the wood, as it breaks down and loses strength you start to feel the spongey effects of this. under the original floor there are supports for the floor. The floor sits on stringers, bulk heads, braces..... with out that support even 1" thick marine ply wood only 4' wide will flex, not good. and the way you described you will be adding a lot of extra weight to the boat not to mention when the original rotting wood in the floor starts to crumble it is going to work its way back to your bilge pump and clog it, hope you have a life vest, i discovered this when i was 9 miles out in the gulf and the bilge wouldn't work, i pulled hand fulls of mushy rotted wood out of the bulge, i just went through this on my boat! cut out the old floor, inspect the stringers/ all wood under the deck. cut out and replace all damaged wood and do several layers of fiberglass over it. on mine after i replaced and glassed i sprayed gelcoat on all the glass under the deck, water will slowly penitrate bare glass but gelcoat does a good job of keeping it out of that new wood. glass both sides and edges of the new wood floor and mount it in place, mark where the bulkheads/stringers are and screw the new deck down. glass around the edges of the floor bonding it to the sides of the boat do a do a bunch of sanding, gelcoat, and do a lot more sanding- have fun
