Tape vs. caulk
My house is finally in the construction stage. I am doing most of the airsealing myself. The sill plate is locked up tight(gasket, Contega HF on the inside seam, Prosoco joint and seam filler on the outside seam, and taped with Solido Exo). As they have framed the first floor, I have noticed that the double top plate is a real source of air leaks. They put a sheathing seam right at that spot as well, so it will continue to be a source of air leaks. What’s the best way to seal it up? Should I tape it inside? outside? Or should I caulk it inside and/or outside? what would interfere least with the framers and drywallers? I still have access to the outside as they have not started on the second floor yet.
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Kevin, do you have a designated location for your continuous air barrier? It sounds like you did a comprehensive job at the sill plate, but you need a plan for the rest of the house. It's often easiest to make the wall sheathing the airtight layer, by taping all of the seams or by installing a full self-adhering WRB. There are various options for the roof or ceiling. If you're using other Pro Clima products, Tescon Vana is a good tape for sealing sheathing seams.
Michael--the continuous air barrier will be the Solitex Adhero on the outside. I just like to make sure my system is redundant.
Note that from a moisture standpoint, interior and exterior air barriers are not equivalent - so there are advantages besides redundancy.
Tape is typically better than caulk.
Kevin, that's great. For redundancy I would move to the interior. Tape is best because it's easier to verify that it's installed well, and it will likely maintain its seal better over time. But Contega HF is good stuff, and less expensive--I'd consider sealing the joint between plates with it, from the interior.