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Join Date: Jun 2011
Location: West Vancouver B.C.
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Re: Choice of USA Grown Wood for Rebuilding
What I saw for a big difference between marine grade ply & exterior was on the exterior there seems to be more voids in between the layers. The exterior ply I got didn't come from a home depot type of store either.
I was snapping after picking up the first sheet of 1/2" marine ply at $85.00 a pop so the next sheet of ply I got was exterior. First cut I was amazed at the voids, thought it was a fluke. Made a couple of more cuts & what was left of the sheet & the pieces got recycled into a staging platform for working on the boat.
The other thing w/ exterior grade ply, it is meant to be covered with something, siding, roofing. The stuff I recycled into the platform is beginning to delaminate but I didn't seal the edges either.
That was my experience with exterior grade ply anyway.
If I could get 1/2" marine ply for $85 I'd use it too. The last time I priced it here it was double that and then some. The exterior I've had has had voids but not like you describe. No ply will withstand being left in the weather unprotected.
The biggest problem with plywood (and lumber) is that the manufacturers have been allowed to set the "quality" standards. The deterioration of those standards over time is a shining example of "free market capitalism" in action.
I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.