Concrete to sheathing seal for a vented crawlspace
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I have a vented crawl space.
I am wondering if the concrete to framing seal is still important in this case?
I am guessing it is because air can make its way under the sheathing and into the wall cavity.
Thanks for the clarification
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Replies
Hey Joe,
Are you asking about the seal between the foundation wall and the sill plate? If so, the main reason to use sill seal is to air seal, but it can also act as a capillary break. Even though your sill plate will be pressure treated, it can't hurt to keep it dry. I've also heard that some of the more robust products are helpful to keep the plate from deflecting as you bolt it to the foundation wall, which will likely have some irregularities.
Or are you asking if it is important to bring your air barrier from the walls to the foundation? With a vented crawl, that doesn't seem like it would be necessary, but I'd need to see drawings of the details to know for sure.
Hi Brian,
I have sill seal already, this not what I'm asking about.
I am referring to the air barrier coming down to the concrete. I am going to tape my plywood seems and am wondering if its necessary to bring it down to the concrete if I have a vented crawl. I suppose air could come through that area and into the wall if I don't.
Joe,
You can also caulk the sheathing to the sill plate. What are you planning to do to insulate and air seal the floor assembly and rim joist?