Waterproofing Plywood for boat deck

[bigeric17]

I'm getting ready to recarpet my aluminum boat. I'm gonna replace the plywood too, you guys ever done this and waterproofed your plywood? how?
I was thinking about painting the plywood with "chassis black" it's kinda like the texture of a bed liner, i think it should hold up and penetrate any water. What do you guys think.
Thanks for any input.
Eric

[MikeD]

not sure about painting it to seal it, but they do make marine grade plywood which is designed for watery environments. abit more expensive and harder to find, but its supposed to last much longer

[mac (Doyle McEwen)]

marine grade plywood that has been sealed on both sides and the edges should work just fine..I don't think any of it can be made completely waterproof, but you should be able to make it last one hell of a lot longer..

mac

[Casey]

I built a small bass boat and I used a water-sealant I bought at Home depot and then then a marine varnish boat at a local boat shop before carpeting. It's been almost 2 years and i've had not one problem to the plywood. No warping or bowing. I live on the central coast and get our share of rain. Hope this helps

Casey

[kazk]

Definitely go with the marine ply. Try coating it with an epoxy based paint or clear epoxy. surfboard epoxy will help it maintain and wear better.

Chris Koda

[Rick K of Ca]

You can go to Home depot and order the marine plywood. You pay up front. It will last a lot longer. Most stores that have wood can order it for you.
Rick K of Ca

[Steve]

I did my decks with marine plywood back in 1997. Ive logged alot of hours in my boat, including fishing in the ocean and duck hunting tons. Decks are still fine. Seems easier to buy marine then have to get sealants and all that stuff.

[ash]

You probably want to get the Marine Plywood then apply whatever you want on top. A buddy of mine decked out a Jon Boat and used the spray on liner. He fished salt water and freshwater he LOVED it cause he could hose down his boat at the end of the day.

The only negative is man it tears up your knees when your re-tieing or culling, other then that its a pretty good deal.

[Whoopbass]

I've converted a couple aluminum rigs with decks.
The first one I did lasted about 8-10 years. I wrapped carpet around the deck cut out before I installed it. Only the bottom was exposed.
The boat has been sitting for a couple years and I noticed it had dry rot pretty bad. I doubt if the plywood ever got wet but just being exposed to moisture will eventually rot regular plywood.
Marine ply wood is expensive. I checked on it 10 years ago and they wanted over $50 a sheet so its probably $100 a sheet now.

There's a guy here in Modesto that was (probably still is) selling 1/2" plywood that used to be signs for KB homes. He had a big stack of it.
One side had the plastic decal covering it and the other side was painted with some sort of black paint. The guy claims it's pretty much weather proof. He said these signs are exposed to the weather for years so they have to be made to withstand it. He said some of the signs have been knocked down into the dirt and wet grass and and the plywood has never warped or rotted. It's grade A plywood with no knots or anything.
He wants $15 a sheet.
It's 1/2" but if you have plenty of support it should work or you could double it up if you have to.
If your interested i'll find out if he still has it and get you directions.

[basstamer]

I did this same thing years back on an old boat I had. I took and cut my plywood (REGULAR plywood) a bit smaller than needed and mixed fiberglass resin and painted both sides and all the fresh cut edges. I also took and put fiberglass mat on all the edges and beefed up where the pedestal mounted. Saw the boat a month or so back and its still as solid as can be. You can buy fiberglass resin for about 10.00 a quart @ Walmart or any auto parts place-same with the cloth/mat.Dont forget to use Stainless Steel screws/bolts/nuts! Good luck
Scott

[basstamer]

I did this same thing years back on an old boat I had. I took and cut my plywood (REGULAR plywood) a bit smaller than needed and mixed fiberglass resin and painted both sides and all the fresh cut edges. I also took and put fiberglass mat on all the edges and beefed up where the pedestal mounted. Saw the boat a month or so back and its still as solid as can be. You can buy fiberglass resin for about 10.00 a quart @ Walmart or any auto parts place-same with the cloth/mat.Dont forget to use Stainless Steel screws/bolts/nuts! Good luck
Scott

[Lugnut]

When I had my aluminum decked a few years back. They used a black resin that completely sealed it before carpeting. Try "Smooth as Glass" in Riverbank they are located just off Patterson Pass rd. near the movie theatre. Jeff would probrably sell you a 5 gallon bucket for a reasonable price.