View Full Version : Plywood floorboards

12-14-2003, 04:20 PM
Anyone have any tips on choice of material for marine plywood floorboards and finishing?

They will be 3/4" thick. I am looking at a choice locally of either Okoume 1088 or Meranti 1088. The Meranti is 20% cheaper...both are 11 plys.

They will see a lot of wear and I plan to paint them with Pettit Easepoxy 1 part polyurethane with the edges sealed with 2 part epoxy resin before the Easepoxy. Non skid will be the Pettit skidless compound (either shaken on or stirred in)

Domesticated_Mr. Know It All
12-14-2003, 05:06 PM
What kind of boat? 3/4" seems overly thick and too heavy for a small boat. Marine grade Douglas Fir might be cheaper, more rot resistant and lighter. Doesn't look as nice but if you're gonna paint it who cares? Look for ply with a thick face veneer. Floors take a beating.

12-14-2003, 05:39 PM
Mr. know it all's post is 100% on the money, couldn't agree more. I would add in my opinion that for a floor, i might suggest ( and this is the only place) that i would ever consider it, would be a high quality exterior douglas fir plywood with one A face. And I would not use epoxy or polyurethane paint, you might find it pretty slick. But instead use plain old porch and deck paint in a oil base with pumice added for slip resistance. But you have to choose from what is available.

12-14-2003, 07:26 PM
As for douglas fir ply, I used the lumber yard exterior grade 3/8 inch and laminated a 1/4 inch of my favorite heart pine with epoxy for the cabin sole. The key to success is to put cleats accross the back side to keep it from cupping. smile.gif Welcome aboard! ;)

Bob Smalser
12-14-2003, 10:14 PM
Depends on the thoroughness of the bottom framimg, but I'm working on a boat now with 1/4" DF plywood floorboards covered on top with one layer of light fabric and epoxy and paint that are perfect for their purpose...plenty stiff yet light and easy to take up.

12-14-2003, 10:58 PM
...... Mdo ply works great- 3/8 to 1/2 inch as long as its supported will be plenty thick- get the paper 1 side only and use a water proofing sealer on the under side o bare wood- pull the boards once a year minimum to clean the bilges and re apply sealer at that time- theyll outlast the boat.

12-14-2003, 10:59 PM
.... I would never use 1/4 inch for plywood floor boards- much too light- and why the hell would any one fiberglass cover a floor board?.....

Peter Malcolm Jardine
12-15-2003, 12:06 AM
The floor boards on my CC are 3/4 fir... I would CPES them first, then paint, then apply whatever surface you want... just my two cents... provided you have GOOD drainage off your floor, and have carefully sealed the edges, the floor should last a long time

Bob Smalser
12-15-2003, 09:01 AM
Originally posted by Amsterdam Shag:
.... I would never use 1/4 inch for plywood floor boards- much too light- and why the hell would any one fiberglass cover a floor board?.....I spose the designer had light weight in mind for this sailboat....but after using it, the boards are plenty stiff, given the framing beneath and the fabric and glass with a tad on non-skid applied makes for a long-lasting, hard surface that can go a number of years without new paint because of fissured plywood.

Dunno what's right for your boat, Clambone....would be easy to throw a piece on there for a test...am just pointing out what somebody else did quite successfully.

Domesticated_Mr. Know It All
12-15-2003, 09:14 AM
My 16 foot Lyman Outboard has 1/4" plywood floor. Thats why I asked, what kind of boat? Pete's Chris Craft is much larger and came with 3/4" ply flooring. The thickness is usually determined by the size and weight of the boat. What was the thickness of the original floor? Ya folla? I'll second the use of porch paint and good shoes for a non-silp floor.

On Vacation
12-15-2003, 09:22 AM
"Depends" Gosh been using this word a lot around here.
size of boat,
width of support of the decks,
configuation of supports,
types of plywood,
floating floor boards, or screwed in place?

What more can be said without a lot more information?
So many questions, so few replies from the original posters???

Domesticated_Mr. Know It All
12-15-2003, 09:40 AM
Not everyone leads a life of leisure like us Oyster. :D I'm sure Clambone will check in after work.

On Vacation
12-15-2003, 09:55 AM
I am actually working. Overseas markets are up, dollars are up, may need to build a bigger boat. May need some help, may require more space, may require more files, more plywood, more glue, more resin, more and bigger trucks, more and bigger trailers. Where does it all stop, this leisure time?? ;)

Keith Wilson
12-15-2003, 10:48 AM
The Meranti I have used is heavier and harder than Okoume, and would probably stand wear better. I presume weight isn't an issue if you're using 3/4. Porch paint is the best thing for floorboards IMO, and cheaper too.

[ 12-15-2003, 10:50 AM: Message edited by: Keith Wilson ]

12-15-2003, 11:34 AM
Thanks to all for your replies. I should have said in the original post that it is a 50 ft boat thus the weight of the floorboards is not such an issue. The floors will be fixed in places with some cutouts for inspection/access to the bilge.

Sounds like Meranti gets the most votes with Fir second and Okuome third.

And yes , I have been busy!

12-15-2003, 01:16 PM
..... the okume and meranti will cost you a bundle- check out 3/4 mdo plywood- about a third the price and will look better painted than either of the above.... you do plan on walking on these foorboards dont you?.......

12-15-2003, 04:03 PM
Best thing about meranti and okoume is the color and grain for bright finishing. If its to be painted I don't see the point. Neither has great rot resistance