Prep wood before laying new carpet?

[KawarthaAngler]

Before any new carpet or under padding is installed, is it common put a sealant coating on the pressure treated plywood (such as an oil based Varathane or Thompsons Water Seal)? Or is it normal or recommend to not put anything on the pressure treated plywood to further seal it?

Thanks.

[Lape0019]

If you are talking about a boat, it is recommended not to use Pressure treated wood period. I know the newer stuff is a whole lot safer but marine grade plywood is usually the recommendation. I do not believe there was any sealer of any kind on the marine grade plywood in my boat and it is still going strong after 12 years.

 

I have seen people use various sealers to help things out but if you use the proper wood to begin with, I do not see a need for it. If you do, I would go with something a little more durable that Thompsons water seal.

 

[KawarthaAngler]

Thanks for the input.

I pulled the front casting deck and small triangular bow piece off my boat last fall to recarpet.  It is a Lowe Fish & Ski 165.

When I pulled it all apart I saw that I needed to replace the wood as well.  It has started to flake and break apart.  It was 1/2 inch pressure treated plywood. 

I watched a recent video on YouTube by a boat manufacturer (I think it was Princecraft) and the video was showing how pontoon boats are made.  The floor of the pontoon boat was pressure treated plywood.

I also stopped in at my local lumber yard and asked what wood guys buy when they come in for redoing their boats.  They said pressure treated is the most commonly purchased, but they do sell at 3x the price marine grade plywood.

From what I saw in that pontoon boat construction video and talking to the local lumber yard, I thought pressure treated was most commonly used.  It may not be the best, but is common.

[Lape0019]

That very well may be the case these days. The older pressure treated stuff had some nasty chemicals in it that would eat through aluminum over time. Like I said, the newer stuff is supposed to be safer but for me, I would still use marine grade (especially if you can get away with just one sheet) just for my own peace of mind.

From what I can tell, there really isn't anything else done to marine grade plywood, the difference is in what type of wood it is made out of and the glue used to bond it together.

 

 

[Fish Farmer]

Far as I know, like said above, pressure treated will affect the aluminum, unless they have charge the chemical..

Marine plywood is made with no knot holes inside the layers of the sheet.

Edited March 29, 2018 by Fish Farmer

[KawarthaAngler]

If it has the chance to affect the aluminum, then if using it ... I guess it is recommended to coat the wood with a sealer?

[Dozer]

Sealing fresh pressure treated wood wont always work.  The chemicals are too fresh and close to the surface of the wood that any penetrating sealer ( you mentioned Thompsons, which is a mineral oil ) will interact with the chemical ( copper + whatever the hell every other company adds )  causing the sealer to fall short of expectation/fail.

[Sinker]

I've had PT wood in my aluminum boat for 10yrs now. No problem. No sealer, nothing. The wood is on PAINTED aluminum though......maybe that makes a difference, but either way, no issues whatsoever. 

 

 

S. 

[HTHM]

Pre drill all of your holes, oversize, and coat the wood with fiberglass and resin. Redrill the holes so resin remains, do all six sides and it will outlast you. 

As far as PT, I would not recommend using it. The glue will break down over time and then the delamination begins. 

Edited March 29, 2018 by HTHM