Rot found during renovation.
MikefromtheMountainsofUtah
| Posted in General Questions on
Does anyone have experience with dealing with some rotted OSB? It took 20 years to get like this and thankfully does not appear to be effecting the building structurally.
Rather than taking down a bunch of veneer stone below where the ledger wasn’t flashed correctly, is it possible to spray a mildewicide behind the veneer stone and just repair/replace the OSB that was right behind the ledger?
My thought is that there is no reason to remove the veneer and replace the osb if I can stop rot and prevent moisture from getting back there.
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Replies
It is structurally affecting your structure as your osb is almost certainly your shear. You can’t save that osb, the binder is almost definitely compromised.
Is the right thing to rip off 700 sq ft of stone veneer just in case?
If everywhere you’ve torn off behind veneer is like that I think it would probably be the safest bet. Of course hard to diagnose from a picture but osb is much less resilient to moisture damage than ply (well some of the newer premium osb are pretty good). You might be able to go from other side to diagnose, as gypsum is easier to fix.
If the OSB is rotten that veneer is coming off whether you take it off or not.
Also doesn't look like any WRB behind the adhered stone. That will fail eventually, might as well fix it now when doing big work.
Adhered stone like that is pretty close to standard 3 coat stucco. It needs 2 layers of WRB and preferably a rainscreen gap. OSB is also not a great substrate for it, any details are skimped and it will fail in short time.
Mike,
What you don't want is to leave things until that rot to gets into your framing or rim-joists. Then everything becomes much more complicated.
It's an almost sure bet the OSB is worse under the stone veneer, which wicks moisture towards the sheathing when it gets wet.
Thanks everyone. It's coming off
Mike
That's too bad. It looks great, but I think you are making the right call.