OSB as air barrier
Steve Young| Posted inBuilding Code Questionson
A while back there were questions regarding the integrity of OSB as an air barrier. Has that been substantiated, or debunked? Any new studies or improvements in manufacturing?
As a side note, I saw ZIP sheeting priced about the same as regular OSB at my local Lowes a couple weeks ago. Go figure.
Steve Young OH
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Replies
People have used OSB as their air barrier before. The weak spot will be the seams, so you have to make sure you're using a good tape. Aside from that, you should be fine. I'd still detail the interior drywall as an air barrier though, belt and suspenders and all that.
The "OSB costs as much as Zip" thing has been pointed out on GBA in the recent past. This has something to do with today's crazy building materials costs, apparently. If you're building today, I would absolutely use Zip since everyone seems to agree it's a higher grade of OSB than regular OSB, and if it costs the same, there is no reason at all to NOT use Zip. It's like a free upgrade, in a way.
Bill