Time for a new floor and???????

[Boomyal]

....If they made it right the first time I wouldn't be havin to go thru this. Are there any substitutes for plywood floor material? Such as composite panels that would be impervious to moisture.

 

[JasonJ]

Re: Time for a new floor and???????

There are materials that can be used in place of wood, but it is very spendy. What you have to ask yourself is how long do you think you will have the boat, how will you care for it? What killed the wood in your boat was moisture being allowed in to soak the wood and then being trapped. Plywood doesn't handle being wet all the time like solid wood can. <br /><br />People have a bad habit of thinking that because it is a boat it can sit out in the rain and snow. That kills a boat quicker than anything else. All that water pooling up in the bilge evaporates and then condenses on the underside of the floor, keeping it wet. The floor keeps soaking the water in, and the rot sets in after that. Also, water soaks into the floatation foam and never comes out. Finally, water seeps in through screws in the floor from mounting objects to the floor. Through bolts in the transom that are not sealed right allow the transom to soak in water as well.<br /><br />The solution? Seal all screws and throuth bolts, and keep the boat under cover when not in use or at least if rain is expected. How old is the boat? If it is like my boat which is 33 years old, I figure it made it 33 years before I had to replace all the structure, I did better job than the factory did, and I take good care of my boats. I know I will get at least another 33 years out of it, but will I have this boat another 33 years? Doubtful. Go ahead and use wood, glass it in really good, seal everything, and take good care of it, it will last as long as you need it to.

 

[Boomyal]

Re: Time for a new floor and???????

JJ:<br />The boat is 28 y/o, never had water puddled in it and whenever I've washed out the inside, I've always tilted it bow high. It has the original floor mat that runs gunwale to gunwale. I suspect that water has gotten below the floor, over the years, from washing it out. I've put several messages out, both here and another forum, for any Mfg's info on how the boat is constructed below the floor mat. How the floor was sealed, type of material, foam type, stringer material, etc etc.. There have been no responses and of course the Mfg is long gone. I'd hoped to get an understanding b4 I tore into it

 

[JasonJ]

Re: Time for a new floor and???????

Sounds like you may not know until you tear into it. More and more boats are being built with composite structure, like preform stringers made of fiberglass with foam sandwiched between, solid glass stringers, all sorts of ways. If you want to spend the cash, you could rebuild you boat that way. I would do it if it were a boat that I thought I would have for a very long time, something that is a timeless classic or performance boat. In my mind (for what THATS worth), the average boat doesn't need all that high tech gee-wizery. If you use wood in the construction and make sure everything is coated with plenty of resin on all sides and edges and glassed in really well, you will be fine. Making sure there is plenty of ventilation in the bilge is a good idea also, cuts down on that condensation forming. Sealing all screws and fasteners is a must. It is hard to win the war against moisture damage, we can only just keep up with it.

 

[BillP]

Re: Time for a new floor and???????

Composite panels are big time expensive...the last I looked at was about $300 a sheet! The alternative is pressure treated wood. Treating processes have changed in recent years and now made it possible to use pt with glass. Greenwood Industries makes a marine pt ply that can be used for floors, stringers and transoms. The last price I got locally in Florida was about $85 for 1/2"ply sheet...this was a special "non stock" order so I don't know what the real price is. Yes, resin will stick to it and many of the boat factories are using it successfully(have been for years). In my opinion this is way superior to using untreated wood...it won't rot even if water gets to it and rot worry is history. I'm just finishing up a complete rebuild using pt in stringers, floors and transom.

 

[JasonJ]

Re: Time for a new floor and???????

Bill, is there any additional drying time for that pressure treated stuff, or can you buy it and install it? It seems like that is the way to go if the resin will stick to it and you don't have to let it set forever to completely dry.

 

[BillP]

Re: Time for a new floor and???????

jason,<br />The Greenwood pt ply is already dried to a certain moisture content and is ready to use as is. There are other mfgs of marine pt ply and I think they are all dried and ready for use. It isn't like the common pt ply you buy at homedepot which is dripping wet. <br /><br />Regular pt ply will work if you can deal with the grade of wood and let it air dry for a few months. Several years ago I contacted a naval architect about this and he recommended air drying for 6 months. I recently used (7 sheets)of some "regular" 3/4" & 1/2" pt ply and air dried it for 5-6 months after cutting the pieces out. During that time I flooded it with acetone several times and ran a fan on it for weeks at a time. It dried enough to my satisfaction for use. The hardest part of this ordeal was storage and keeping the wood from warping. <br /><br />Surprisingly enough, the "regular" pt ply had almost zero defects and was good stuff. This is one of the only products I know of that seems to have gotten better...it wasn't anything like the cdx pt decking I used to buy years ago. <br /><br />Here's a link to the APA through glenL.<br /><br /> http://www.glen-l.com/wood-plywood/boatbuilding-plywood.html

 

[JasonJ]

Re: Time for a new floor and???????

Cool. I used regular ACX on my last project, didn't figure I would have the boat so long as to need the superior properties of the pressure treated, but if I ever come across a project that I feel I will have for a very long time I think the pressure treated and using epoxy rather than poly is the route I will go. My current rig has performed outstanding, I don't let water stand in it, water never seeps into it. When I did it I made sure to leave no exposed wood, it is all glassed or at least has a few coats of resin. It is my understanding that water can get past poly resin, but I figure if I get 3 to five years out of the boat then it will have been worth the effort. I also figure the original non pressure treated poorly glassed structure lasted 33 years so I have a bit of time...