Three tapes compared
i recently came across zip system tape, and it is relatively affordable but want to use it for cdx plywood (not zip sheathing) Wondering if anyone has used it on that surface, and how it compares to tapes like tyvek butyl flashing tape, and 3m 8067 acrylic flashing tape.
EDIT: basically what I’m getting at is this: zip tape is relatively affordable and I’m open to switching to it from 8067. And as an aside, I haven’t tried tyvek butyl flashing tape but heard good things and wondering if someone has opinions on just these few tapes head to head, if you will.
Secondly, I HAVE however used tyvek’s flexwrap and do like it, but again I am open to switching to zip stretch tape if it’s a much better product. Again, on cdx.
just wanted to gather a few opinions on these tapes, thanks!
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Replies
I haven't heard anyone say anything bad about the Zip tape, and it'll work fine on CDX. It is an acrylic tape, so it's more similar to the 3M (which is also well-liked).
This is a good overview on acrylic vs butyl tapes, and when they are appropriate: https://www.buildingscience.com/documents/insights/bsi-067-stuck-on-you
Both Martin and I have done our own "field testing" of PSA tapes; you can find my work on this here: http://www.buildinggreen.com/stickybusiness.
I did not test the 3M 8067 but Martin did. I simply could not find it, strangely enough, when I did my last round of testing. But around my neck of the woods, everyone lauds the 3M 8067 tape.
In my testing, nothing performed as well as the ZIP tape. My tests are NOT conclusive by any means but what I hear as I get around is that while ZIP tape is designed for ultimate compatibility with the ZIP sheathing polymeric outer layer, it is an aggressive tape on many surfaces, including plywood and regular osb. And remember, the key to all PSA tapes is PRESSURE. As you press on the tape, it "wets" ("liquefies") the adhesive so it can maximize surface area contact with the substrate, significantly increasing the total surface are of adhesion.
Peter
Maybe related, how do you get rid of air bubbles in flashing tapes?
I mean, my tape job has to be nearly flawless but even then there’s always some bubbles and wrinkles, especially when you consider uneven surfaces you are spanning, nailing flange, nail heads etc...
Am I the only one? Will those bubbles cause problems down the road?
Tips?
Thanks
The key to a good application is to “roll” the tape on and keep a little bit of tension on the tape as you go. Keep the tape parallel to the surface as it comes together. The occasional large-ish bubble can be pushed to the edge of the tape with a hard roller or a round, hard object like the handle of a screwdriver. Tiny bubbles aren’t worth worrying about.
It’s not that much different than applying packaging tape. Keep it straight, keep it taught, keep it parallel to the surface, push it down with a roller.
Bill
As I replace siding on my house, I have been zip taping CDX then applying tyvek over. No problems so far. I had the tyvek bare for 4 or 5 weeks over the zip tape plywood waiting on a window and it looked great during the window install still.
I did use 3m tape for the window.
So when I did pvc corner trim and siding next to it, I put a strip of zip tape vertical next to it, under the LP smartside lap to pvc trim joint. Backup flashing when the caulking fails.
EPDM cover tape with primer rolled on a 45 will not melt, bleed, peel, or let water in even on OSB