Pressure treated plywood?

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lsheaf
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Pressure treated plywood?

Post by lsheaf »

Hey guys, I’ve heard that using pressure treated wood on a boat is not recommended (also read this in a article by west system). Has anyone used pressure treated and had any issues?

Logan
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atomvoyager
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Re: Pressure treated plywood?

Post by atomvoyager »

Many people use PT wood on boats. The main issue is that unless it has dried for a long time the chemicals near the surface repel paint and epoxy. Cheaper rot-prone woods are used for PT and while the treatment prevents rot, the treatment only goes so deep and where you cut it may not be protected. And the wood can warp more than others as it dries. Some of the complaints against PT are that it corrodes 304 type fasteners and has nasty chemicals like arsenic but that was years ago and I believe the formulas have changed so those aren't as much a problem. I try not to use it for most jobs I do, mainly because of the adhesion issues but I have used it a couple times successfully when I knew it had air dried a year or more.
I haven't read the West System article so maybe they have something else to say about it?
svMira
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Re: Pressure treated plywood?

Post by svMira »

In our area, central Canada, the quality of the plywood isn't good enough to start off with to bother. Because it is expected to be used exterior and often related to decks and such, the plys are few and large, voids are common and the stuff splinters like crazy. I can't think of a place on a boat that I would have need for wood of that poor quality.
Marvin - s/v Mira - 1971 Pearson Wanderer #174
svmira.ca
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