Is tape permissible between framing and the party wall for air sealing?
We are building a Passive House duplex and have encountered bunch of air leakage around party wall. We don’t have to reach Passive House standard for each of the units separately, only as a whole building. But currently, our party wall does not have any air seal crossing between two units. This opens up the possibility of air getting in somewhere at the top end of it (at the roof) and traveling down to edges of the party wall touching the whole building enclosure/exterior plywood. We have difficulty sealing these vertical contact points due to other framing being in the way. Is it permissible by code to add tape to seal the ~1” gap between framing and the party wall? I attach a picture of the corner at ceiling and at party wall and of the horizontal gap at ceiling and the party wall. We would like to run tape to cover these gaps.
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Replies
With Proclima Contega SL tape (fleece, airtight, triple-release double sided sealing tape) we were able to successfully seal another area which had wall studs in front, like on this wall.
Lucyna,
Air leaks at party walls are a huge problem in many buildings. It's good to focus on getting these details right.
There are two aspects to this question: the air sealing aspect and the code-compliance (fire safety) aspect. I wouldn't implement any measures in this area without first consulting with your local building department, to make sure tha you understand how local codes are interpreted and enforced.
Lucyna,
It's a good idea to remember that sealing all the intersections of materials on party walls also makes a tremendous difference to how well they perform from a sound abatement point of view. Substituting acoustical sealant for tape wherever possible will aid this.