by Mark McD » Fri May 08, 2009 7:35 am
I've been in the trades for over 25 years and have used osb and plywood to build many, many things. The problem isn't a products supseptibility to moisture, it's the way it's used. I have no qualms whatsoever about using OSB for ttt construction given the fact that it's only a substrate,. What you use to clad your ttt and the methods used to waterproof are more improtant than what's underneath. The fact of the matter is the substrate is not supposed to get wet, if it does, it doesn't matter if it's osb or plywood. If your substrate is getting wet your problems go beyond the type of material used.
BTW, OSB and exterior rated sheathing are made using water resistant glues, the cheap Home Depot " cabinet grade" birch panels are not. The latter type of plywood will delaminate much quicker than osb or exterior ply when exposed to moisture. Food for thought.
And I've used foil faced osb, paper faced osb, resin faced osb. They hold up okay.
If you want to use a good exterior grade faced board there 's a product used by signmakers that has a resin impregnated paper adhered to it that holds up really well, But its pricey.
I like turtles
Mark
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