How to air-seal the floor of a finished room above an attached garage?
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The framers are well on their way to being finished within a week and as they put the subfloor down on our bonus room above the garage it occurred to me that I do not have a plan for air-sealing between the garage ceiling and bonus room floor. Overall, I am taping the OSB sheathing as the primary air-barrier but I am not sure if I should also tape the top of the bonus room subfloor as it will be walked on and could interfere with the flooring later on.
All suggestions on how to air-seal this space are welcomed and if it matters, I am in central NC (4a).
THX!
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Replies
You should be able to caulk the seams in the subfloor and where it meets the sole plate at the wall and get a good seal.
I also like to air seal the ceiling drywall of a garage. Garages can be noisy and smelly and have a heightened fire risk so you want a good barrier. The ceiling tends to have few penetrations anyway.
I’m planning to finish the my room above the garage as well. I was planning to air seal the Advantech subfloor with zip tape before I install the flooring (most likely lvp).