# Paint grade exterior plywood



## Termite (Apr 13, 2008)

Don't be fooled by the term "exterior" when dealing with plywood. Just about all plywood on the market has "exterior" glue these days, and I promise you that exterior glue isn't going to hold up long outdoors without proper finishing/flashing. When I was in the lumber business, we sold "marine grade" exterior plywood, and people always bought it for exterior applications because it had the word "marine" in it. The only thing that made it special was that it had no voids in it...Whooptydoo...It will de-laminate just as fast.

Ok, off my exterior plywood soap box...

What you use depends on the look you want. If you want smooooth, go with MDO plywood. That's what they use for a lot of road signs. It is meant to paint, and looks better than anything once painted. No grain structure in the finish. Prime and paint.

Plain old AC grade plywood will finish up nice. Sand it lightly first, and prime and paint. 

Roseburg Forest Products (and others) make a meranti-faced product in various thicknesses and patterns that resembles rough-sawn fir. It is a good exterior product. Prime and paint. 

Another option is Louisiana Pacific Smart Siding. They make at least a couple different varieties. It has borate in it, and is pre-primed. Good stuff for outdoor use. 

Whatever you use, if you're going to get it wet at all, be sure to flash it properly, and prime all the faces and edges.


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## Clutchcargo (Mar 31, 2007)

Thanks KC, 
MDO it is.
Is that the plywood with the paper/fiber exterior veneer layer?


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## Termite (Apr 13, 2008)

Yes it is. You'll probably have to get that from an actual lumber yard...HD and Lowes don't keep it around here at least.


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