Birch Ply Question

[zapj]

I was at Lowes today looking at birch and lauan plywood. To my surprise neither had any information grading stamps as normal plywood carries. The lauan had a pricing tag on the metal sorting rack which stated it was moisture resistant. The Birch had a tag stating for interior use only. I had wanted to use stained birch on my exterior then seal it with Minwax Clear Seal. Will this procedure or painting allow me to use it in an exterior application or is there exterior glued Birch available somewhere else? I haven't decided yet to stain or paint but was not looking at epoxy.

[Ira]

I was at Lowes today looking at birch and lauan plywood. To my surprise neither had any information grading stamps as normal plywood carries. The lauan had a pricing tag on the metal sorting rack which stated it was moisture resistant. The Birch had a tag stating for interior use only. I had wanted to use stained birch on my exterior then seal it with Minwax Clear Seal. Will this procedure or painting allow me to use it in an exterior application or is there exterior glued Birch available somewhere else? I haven't decided yet to stain or paint but was not looking at epoxy.

The birch said for interior use only? Were you looking in the paneling section, or with the plywood?

If you look at the side skins in my avatar, which won't help you for the roof at all (it won't bend without incredible efforts), that's beaded birch. Yes, I found it in the paneling aisle of HD, but it's not composite/particle board paneling.

Since you're in Florida like me, it's not going to be easy finding bendy birch. I had mine shipped from Massachusetts, for the roof.

www.boulterplywood.com

And it's a lot less expensive shipping it from there than you would think.

I wouldn't concern myself with seeing grade labels for the skins though, especially not luan. As long as you seal it well. (I varnished.)

[zapj]

Thanks Ira, I was in the plywood section and both the 3/4" and 5.2 mm 4x8 panels were marked," will accept stain or paint"; "interior use only."

[mikeschn]

I think Steve F might have an answer for us...

Mike...

[48Rob]

Hi,

Exterior grade ply will fare better outside than interior grade (the difference is in the adhesive used to hold the ply's together).

Exterior grade doesn't mean you can mount it "outside" and it will stay in the same "as new" condition as it was when you bought it, only that it is more resistant to de-lamination because of the higher moisture levels outdoors, or on a roof, or whatever the application.

What is really at issue here, is how the wood will be sealed, or protected from the elements.

IF you take the time to seal all 6 sides well (multiple coats) until there is no chance moisture will find a way in, then you will be fine.

You could cover your trailer in cardboard, and have no trouble as long it it was properly sealed.

It is possible that someone makes an exterior grade Birch, but I have never looked...

Rob

[Ira]

Wait--I lost something in the translation, Rob.

3/4" birch?

I thought we're just talking skins here.

[Ira]

Hi,

IF you take the time to seal all 6 sides well (multiple coats)

HAH! I FINALLY GOT YOU, ROB!

Your TD is too gorgeous for me not to say this:

There are only FOUR sides to seal on a TD wall.

Yeah, I know--you're technically 100% right. But I couldn't resist.

[48Rob]

Ira wrote;

HAH! I FINALLY GOT YOU, ROB!

Your TD is too gorgeous for me not to say this:

There are only FOUR sides to seal on a TD wall.

Yeah, I know--you're technically 100% right. But I couldn't resist.

Darn, you sure did!

You're a quick thinker tonight!!

Rob

[Steve Frederick]

I think Steve F might have an answer for us...

Mike...

I've built two kayaks and now, four T/D's with common lumber,in part, or whole, sealing all exposed surfaces in epoxy.
My strip kayak is 5-years old, and the pine, and ash accents I used are as nice as the day it left the shop! (there is a bit of patina developing)
The Stripper is maple ply, covered in epoxy/'glass, The'Diners, both birch, covered in epoxy/'glass. The current project for Peg, is Cherry, Hickory, and Mahagony..You guessed! Sealed in epoxy/'Glass.
Unless the surface sustains damage that exposes raw wood, I am very confident that there won't be any water damage.
Key, IMHO, is that you seal all edges of the ply. I use a very thin, penetrating epoxy, that wicks into the edge grain very well. The epoxy turns the wood into plastic in that area.

[zapj]

Thank you for the opinions I'll stay with the birch for now and just plan on spending some time making sure it is sealed.

[GregB]

Steve,

Do you epoxy all your ply before the build and after cutting to size or wait until all is assembled then apply the epoxy? (I know, I know, I have your CD but my DVD reader is all wonky so I can't refer to your manual)

GB

[angib]

Key, IMHO, is that you seal all edges of the ply. I use a very thin, penetrating epoxy, that wicks into the edge grain very well. The epoxy turns the wood into plastic in that area.

And I would add my former boss' obsession of applying each mix of epoxy more than once - even if you've only got 5 minutes 'open' time before it gels, you can easily apply the epoxy 5 times to the exposed edges and each time it will wick up some more resin. That way there is the minimum of air voids in the end grain that will subsequently draw in moisture.

Andrew