Boat flooring

kat-a-tonik

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Ok, im going to put a floor in my boat, instead of buying costly marine plywood, I have quite a bit of popalar lumber, sense it is water and pest rasistant couldnt I seal and use it
 

Starcraft5834

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Re: Boat flooring

there's a reason why...

"Marine grade plywood is assembled gap and void-free in all layers & laminated together with special, water-proof glue that holds the various layers together. When immersed, water has absolutely no effect on the glue or the strength of the lamination of marine grade plywood. Marine grade plywood will not commonly delaminate, bubble, buckle, or warp. Upon cutting marine grade plywood, no voids will be discovered on the cut edges. It is also usually constructed of harder woods such as Douglas Fir, or Western Larch.
Marine grade is a superior grade of plywood & a substantially better product. "

you can use what ever you want.. just dont expect it to last very long...........
 

Grub54891

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Re: Boat flooring

I suppose ya could,but I know if I saw it it would look wrong. What type of boat?
 

Ned L

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Re: Boat flooring

For average small boat decking there really is no need or reason to go with "Marine plywood". Exterior A/C (or many times B/C) will work just fine. Marine and exterior use the same glue. The biggest difference is that in marine plywood there are no voids in the inner layers (they are all filled).
********* I would NOT use poplar for anything on a boat because it has very poor resistance to rot. It is nice for interior cabinet work because it has a nice mild uniform grain pattern and is easy to work with.
 

further

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Re: Boat flooring

+1^^^ Exterior plywood is good. Try Arauco brand ply if you can find it where you are. Very good quality, no voids, 7 layers and exterior glue. Any exterior ply is good though as long as its properly sealed.
 

JASinIL2006

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Re: Boat flooring

A good alternative to marine grade plywood is Aurauco plywood. It is not as cheap as regular exterior plywood, but it quite a bit less than marine grade. It also has almost no voids, and the plies are thinner, so you get 7-ply board where you normally would have 5 plies. I can get it for about $30 per sheet at a local home improvement store. Good stuff.
 

Bondo

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Re: Boat flooring

Ok, im going to put a floor in my boat, instead of buying costly marine plywood, I have quite a bit of popalar lumber, sense it is water and pest rasistant couldnt I seal and use it

Ayuh,.... Yer kiddin', Right,..?? Poplar rots at the sight of water,.... 'n it has little to no strength,...

I'd use sealed CDX plywood, before poplar,....
 

jbcurt00

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Re: Boat flooring

Ok, im going to put a floor in my boat, instead of buying costly marine plywood, I have quite a bit of popalar lumber, sense it is water and pest rasistant couldnt I seal and use it
As many others have mentioned, poplar isn't a wise chioce. Same 14ft tin boat you posted before:
beams

What did you decide to do about the bench seats:
Those seats are part of the boats structure......
And the flotation foam beneath them?
 

Woodonglass

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Re: Boat flooring

Been working wood for over 40 years. Poplar, as stated, is an extremely poor choice for the Marine environment. Woods with High Resin Content such as Southern Yellow Pine, Douglas Fir, White Oak, Teak, Mahogany or Spruce are good choices. The best choice for your application, would be, as previously stated, the Aruaco Brand of Ext. Grade Plywood.

But as always, It's your boat and you're free to do with it as you see fit!
 
Last edited:

jigngrub

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Re: Boat flooring

Ok, im going to put a floor in my boat, instead of buying costly marine plywood, I have quite a bit of popalar lumber, sense it is water and pest rasistant couldnt I seal and use it

You can, and since it's a small inexpensive aluminum boat I don't think it would be that bad of a build. If you seal the wood really well and keep the boat covered it'll probably last several years.

... but if you don't do much to seal/preserve the wood and leave it exposed to the elements it won't last very long.

Since you're saving money by using free wood I suggest you seal it with epoxy resin and then paint it with nice slip resistant paint.

My main concern with that boat would be with doing away with those plank benches and building some enclosed benches I could fill with floatation foam.
 

kat-a-tonik

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Re: Boat flooring

I decided to keep the bench seat I am going to incorporate them into a front and rear deck.
 

kat-a-tonik

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Re: Boat flooring

Thanks for all the advice, I will be going with preasure treated wood, the boat is always under tarp when not on the water so I thing the preasure treated will serve the purpose, I am going to build a deck in the front and back with a floor in the middle and will add extra foam under floor and decks
 

Bondo

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Re: Boat flooring

Thanks for all the advice, I will be going with preasure treated wood, the boat is always under tarp when not on the water so I thing the preasure treated will serve the purpose, I am going to build a deck in the front and back with a floor in the middle and will add extra foam under floor and decks

Ayuh,.... Pressure treated is as bad as poplar, for different reasons,...

The chemicals used to pressure treat the wood,... Rots the aluminum of yer boat,...
 

jigngrub

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Re: Boat flooring

Ayuh,.... Pressure treated is as bad as poplar, for different reasons,...

The chemicals used to pressure treat the wood,... Rots the aluminum of yer boat,...

I would consider the pressure treated a lot worse than the poplar, at least the poplar won't eat the aluminum up.

Installing pressure treated wood in an aluminum boat is about the worst thing you can do to it.
 

Ned L

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Re: Boat flooring

Ageed, pressure treated is not a good choice. The salts used in the preservative is bad news with aluminum. And as for the idea of coating poplar with epoxy, you will spend more money on epoxy than the poplar is worth.
 

theoldwizard1

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Re: Boat flooring

Boat floor in fiberglass boats ARE a structural member. They help prevent the sides from bowing out.

Exterior plywood is acceptable if you cover all sides with fiberglass and polyester resin. Even on a metal boat, it is recommended that you apply 2 or more coats of marine spar varnish/urethane to all side of your plywood floor before installation.
 

flipbro

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Feb 8, 2013
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Re: Boat flooring

Hmm i dont think preasure treated is what you want in a tin boat! Im no expert but theres something in the pressure treated ply that dont like alluminum an will cause corrosition! why not just use the exterior ply and coat it well with resin Done??
 

kat-a-tonik

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Re: Boat flooring

Ok, i'm no carpenter but I thought preasure treated and exterior plywood were the same thing
 

jbcurt00

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Re: Boat flooring

Nope, not the same:

PT plywood
Note the description:

  • Pressure treated for exterior above ground use
  • Treatment meets AWPA (American Wood Protection Association) standards
  • Limited lifetime warranty that protects against rot, decay, and wood ingesting insects
  • Easily painted or stained: recommeded to wait 60 days after installation
  • Hot-dipped galvanized or stainless-steel fasteners and fittings are recommended
  • Safe for use around humans, pets, plants, and vegetables
  • Specie of product is Southern Yellow Pine
  • HT (Heat Treatment) on grade mark: wood is subjected to high temperature kilns before treatment

^^^not what you want to use.

Arauco Plywood
Description: AraucoPly Sanded ACX panels are laid up on a composed core using exterior PF resin..................

If they are a local supplier, Menards usually stocks Arauco ply, but any exterior ACX plywood is a good alternative as well.

MDO is also a good choice

You can of course use marine grade plywood, but IF you can find it, it is usually very expensive compared to the above choices.

Even if you use marine ply, IMO, you should still seal it w/ epoxy or spar before applying either a painted finish/topcoat, carpet or vinyl, so instead of buying just 1 sheet of marine, you could probably buy all the sheets you'll need for your project for the same money using Arauco or other ACX plywood. Many find it difficult to get ACX, so they choose BCX ply. It's not quite as good a choice, and unless there were no other alternatives, I wouldn't use it.
 

heycookieman

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Apr 13, 2009
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Re: Boat flooring

Thanks for the heads up about the treated plywood. How fast does it eat the aluminum? I put it in my 14' last year.
 
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