Air barrier continuity at top plate
tjones1014
| Posted in Energy Efficiency and Durability on
We’re renovating our 2001-built home in the N. GA area (climate zone 3A/4A). We’re redoing the exterior, so we’ll be able to tape all of the OSB seams for our air barrier. Where we’re running into confusion/issues is with how to make it continuous at the top plate. The roof trusses that overhang at the soffit (vented attic) make taping the seams complicated/near impossible to get a continuous seal.
1. Is leaving the top untaped/unsealed a no-no?
2. If sealing the top is a must, is there a way to do this from the interior? Or any other suggestions for how to tackle this?
Thanks so much!
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Replies
Normally you would have a strip of housewrap or wide tape over the top plate before setting the rafters.
For an existing house, this is harder as those pieces are in the way. You can still do an 85% job by taping the top of the sheathing with short pieces of tape to the top plate. Not much you can do about the rafters, you can try a bit of caulk around that, but in your warm climate, I would not loose too much sleep over it. Instead of tape, another option is to seal on the inside with flex caulk at the top of each stud bay.
You can than seal the ceiling drywall to the top plate for air barrier continuity. You can use something like drywall gasket foam for this.
Make sure to seal any holes through the top plate (ie wiring or plumbing) before any drywall goes on the walls.
tjones,
I'd caulk the top of the sheathing in each bay, and go down the studs about 6".