Was reading the simpson seismic upgrade guide found here:
http://www.strongtie.com/ftp/fliers/F-PLANS07.pdf
and I was wondering why they would specify ventilation holes in plywood that is being fastened to the interior of studs. This assumes the house is old and has no plywood on the outside to counter lateral earthquake forces.
The only reason I can think of to have the holes is to assume that the plywood is going to be hot on the int side and cold on the ext side and condensation will form. This assumes that the cripple wall the plywood is being install on is not insulated or vapiour barriered – otherwise the cold would stop on the ext side of the insulation. If one were to insulate and vb then I think the ventilation holes are not needed.
Thoughts?
Thanks,
learner
Replies
Greetings learner,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again which will increase it's viewing.
Perhaps it will catch someone's attention that can help you with advice.
Cheers
— estimating the pecuniary value of every man's labor at one dollar a day, for if some receive more, others receive less; — so that he must have spent more than half his life commonly before his wigwam will be earned. If we suppose him to pay a rent instead, this is but a doubtful choice of evils. Would the savage have been wise to exchange his wigwam for a palace on these terms? .
Parolee # 53804
The other this to assume is that there is no vapor barrier covering the crawl space floor. If your crawl space has a vapor barrier on the floor that would also cut down on the interior moisture.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
The specific case for me is that the cripple walls are about 4' and the poured concrete foundation walls are about 3' above slab level. So I have a full basement despite the cripple walls. I had the foundation underpinned and the mudsills archored into the foundation walls but I didn't have / didn't know to have / gc didn't tell me to have shealthing installed. The basement is now finished - dw, paint, etc. The exterior is stucco over wood but just wood siding boards IIRC. There is one area that is unfinished that I could have shealthing installed - the unfinished staircase - but I am not sure how much good that would do.
I live in SoCal, which is pretty much a desert environment, so I can't speak you your specific areas water vapor issues.
I recently redid our master bedroom, and applied sheathing on the interior side of the studs, then applied drywall over that. No concerns about having to hit a stud with the drywall screw!
How long ago was your home built? There may have been sheathing applied to the exterior under that stucco with wire lath nailed over the exterior vapor barrier.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
1920ish. When I had the underpinning / basement finishing done I had them open up the walls and insulate. I could see the exterior shealthing and IIRC it looked like wood siding boards though it might just have been tng boards, in either case insufficient for seismic requirements. The exterior vapour barrier is just tar paper. Though I do have some concerns about how the contractor finished the service penetrations - ie spray foam to seal holes on the exterior, holes large enough I could stick my hand into. I likely need to get a stucco guy in to properly repair them.
If you have drywall on the inside of those walls, I don't see how you would have a problem with OSB. BTW, you could also just sand the printed on labels off the sheathing and cover it with a varnish if you wanted a wood finished basement space. OSB with a coat on it looks surprisingly good.Rebuilding my home in Cypress, CA
Also a CRX fanatic!