Seal the bottom of the sheathing to to stem wall?
BrunoF
| Posted in General Questions on
I have regular 2 x 6 stud construction with OSB that will be taped as my primary air barrier. Since the brick is too irregular to tape to, is there any reason that I should not put Sealant in between the bottom of the sheathing and the top of the stem wall to create an air barrier?
pic attached.
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Replies
Sealant would work if it remains adhered and flexible. I recommend Pro Clima Contega HF for that kind of application. Depending on the size of the gap, you might want to use a backer rod--the sealant should be no deeper than it is wide.
Could also use something like Prosoco Fast Flash, overlapping onto the OSB and brick by an inch or two each.
The nice benefit to liquid flashing is if there is a big gap, or little gap, or no gap, and if the OSB is in-plane with the brick, or out-of-plane with the brick, it still works no matter what.
May still need a backer rod depending on the gap size, for all the normal reasons that sealants would need a backer rod. If it's a small gap, backer is likely not needed (see application instructions).
I have used this method to tie ZIP sheathing to concrete for WRB and air sealing, and it's easy and effective.
Thx. I have a bunch of Dymonic 100 and Contega HF on-site and think that the Dymonic might work best since it can be used as liquid flashing and as a sealant for concrete expansion joints so backer may not be needed.