Wrapping Air Barrier Under the Trusses – Best Tape/Fabric Solution?
idahobuild
| Posted in Energy Efficiency and Durability on
Hey All,
What would be a good tape, or fabric, solution for wrapping the exterior air barrier from the sheathing under the trusses and to the interior ceiling. I was thinking of using Wigluv 300 (12″), but it doesn’t appear as though the tape has a split adhesive backing; or other way to protect the adhesive on the tape after one side is set.
Thoughts and suggestions appreciated.
Thanks.
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Replies
I've used 9" 3m8067 for this. You can also use a strip of heavy duty house wrap taped to the outside wall.
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Siga sells 18" rolls of their Majvest WRB and the self adhered Majvest for these types of purposes. Builders have also put the membrane between the double top plates in the wall so the membrane is protected by the wood. Using wood blocks installed before the trusses to set the truss spacing also help as there is less dragging of the trussed across the membrane.
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What I've done is install blocking between the rafters at the wall and staple the tape to it. Once the ceiling air barrier goes up, remove the backing (bit fussy because it tears at the staples) and push the membrane into the tape.
You sketch is simpler than what I've done, I would use that.
Great help!
Since I will be on site during the build, my plan is to ask the framing crew to allow me some time after the walls are up to apply the WRB, as an air barrier, over the top plate prior to setting the trusses. I'll ask them to be as careful as they can during truss placement. That may be a pipe-dream, but I'm sure they'll do their best. Then, after the trusses are installed, I can go around with a ladder and inspect for tearing/holes.
The info. you provided sent me down a good Google path and I found a couple of other options as well.
On the interior side of the tape the sticky part will be facing the floor -- which seems like that is the wrong direction. So, what trick would I use to adhere it to the ceilings Air barrier? Do I just cut it to length and wrap it around the inside of the top plate and press it down? Then tape the ceiling's air barrier (see atch'd image)?
If that is the case, and assuming the framers are applying the sheathing prior to lifting the walls, I can adhere the 18" WRB to the wall prior to lifting. Then, go back prior to truss install and tape the joints. Though I'm not sure that would be easier.
Thanks
Great help!
Since I will be on site during the build, my plan is to ask the framing crew to allow me some time after the walls are up to apply the WRB, as an air barrier, over the top plate prior to setting the trusses. I'll ask them to be as careful as they can during truss placement. That may be a pipe-dream, but I'm sure they'll do their best. Then, after the trusses are installed, I can go around with a ladder and inspect for tearing/holes.
The info. you provided sent me down a good Google path and I found a couple of other options as well.
On the interior side of the tape the sticky part will be facing the floor -- which seems like that is the wrong direction. So, what trick would I use to adhere it to the ceilings Air barrier? Do I just cut it to length and wrap it around the inside of the top plate and press it down? Then tape the ceiling's air barrier (see atch'd image)?
If that is the case, and assuming the framers are applying the sheathing prior to lifting the walls, I can adhere the 18" WRB to the wall prior to lifting. Then, go back prior to truss install and tape the joints. Though I'm not sure that would be easier.
Thanks
for the db - This is not a duplicate.