Tape widths
I’m doing some air sealing on plywood seams using 3 m flashing tape. Is there some standard range of what the width of the tape should be. Like wall to ceiling edge seam or floor to wall edge seam or even just the seams between two sheets of plywood. How does a person determine an appropriate width to use? Thanks
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Replies
Smokey,
Good question. I think in most cases, it's just common sense or judgment that prevails here.
I think that 3-inch wide tape is wide enough for ordinary seams, but wider tape makes sense at wall-to-ceiling seams.
I'd be interested to hear from other GBA readers on this question.
Smokey, because high-quality tapes are expensive, it's an economics question--what is the narrowest width that allows you to do the job. Manufacturers may recommend X" of coverage on each side of a seam but I don't know of any examples. I agree with Martin; in most cases, tape in the 3" range is good, but even 2 3/8" (or 60mm) width is more common among the European tapes. Sometimes wider widths are better for taping windows or wall-to-foundation joints.
Thanks for the help. Ill just go with the 3 inch except for the wall ceiling and wall floor ill use 6inch
6 inch is massive overkill. We used 2" at wall to ceiling and wall to floor. Seemed like plenty.
@Michael
ZIP system requires their min 3-3/4" tape. Granted that's their own re-branded third party tape (Huber doesn't manufacture the tape).
Good point, John. 3M makes Zip tape and there isn't a narrower version than 3 3/4" so it's pretty hard to screw that one up. On a recent project I designed the contractor used 3M 8067 All Weather Flashing Tape, 3" wide, on plywood seams and tested at 0.12 ACH50. At Ecocor, where I used to work, we used 2 3/8" Pro Clima Tescon Vana extensively and almost always tested at 0.4 ACH50 or lower.
The real key with any acrylic-adhesive tape is that it needs to be rolled or "paddled" to achieve full adhesion. I recently described it to someone as, imagine the acrylic adhesive is a bunch of little balls that need to be burst in order to release the adhesive. I'm not sure about the chemistry but I believe that's not far from an accurate description. Then you have to wait 24-72 hours for the adhesive to fully activate.