Zip sheathing: tape or fluid-applied?
lance_p
| Posted in Energy Efficiency and Durability on
For those who’ve used both (or know lots about them), what are the pros and cons of Zip system tape vs their fluid applied sealant?
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Lance, I've used both on my house during construction.
Zip Tape:
Pros: Cheapest high quality tape around and is readily available at any lumber yard. Great for sealing gaps in sheathing quickly as there is no paper backing like the European tapes or 3M. Most framers appear to be familiar with it. It is really tacky and will be there forever if applied properly.
Cons: It is not vapor-open like the European tapes. (Huber might be developing a vapor-open tape though....) Without a paper-backing, its hard to use it for tricky air sealing tasks such as corners. You aren't going to cut a bow tie with it! Framers may apply it willingly but making them roll it consistently/properly was a problem for me. I found it difficult to know for sure if the second story sheathing was both taped AND rolled when viewing it from the ground. Also, if the sheathing is damp then you probably need to wait until it drys before applying the Zip tape.
Zip Fluid:
Pros: Great for flashing doors and windows. In our case, the people that we hired to install our large, sliding door accidentally ripped our flex tape in several areas. This didn't happen with with the fluid applied barrier. As a new builder, I was amazed at how much our high-performance doors leaked on to the sill in heavy rain- even with two foot overhangs. In the future, I will use fluid applied first and then add the flex tape over it for a belt and suspenders approach.
Another pro of the fluid applied is that unlike tape, you don't have to worry about whether or not it was properly rolled when applied. If it has been smeared on to the seam, then that seam is likely sealed. Also, If the sheathing is damp, then you can still apply the fluid flashing! This helps in speeding up things on the job site.
Cons: It is expensive and a bit more time consuming to apply. Also- Huber doesn't publish whether or not their product is vapor open. Using it to seal sheathing gaps seems excessive to me but it would certainly result in a high quality seal.
Conclusion: I love both! I would stick to Zip tape for sheathing seams and fluid applied for fenestration flashing. I would also use a flex tape over it to be safe. (I personally like the Tyvek flex tape better than Extoseal and Huber's stretch tape.) Buy 5 or more J-rollers so that your framers have them laying around every where.
We’re not pro’s, but our under-construction home just finished drying-in, and we used both Zip tape and Proseco Seam and Joint Filler. We would reiterate several of the points that Mr. Evans made. First, the builders DID NOT roll the Zip tape, they applied it with a roller/dispenser that applied “some” pressure, but many portions of the tape weren’t firmly or completely pressed onto the Zip sheathing. We ended up buying a roller to do the job ourselves. We also had several areas where the Zip tape had been abraded after it had been applied – either during window installation or from the ends of the ladders.
Two areas where liquid flashing was a much better solution was; 1) where the Zip sheathing and concrete foundation (almost) met. The poured concrete forms had a brick pattern, and no tape would seal all those wavy ridges, whereas the liquid flashing did a great job. 2) overdriven nail heads. A putty knife and sausage gun made quick work of all those nail heads. It would have been a frustrating task to cut and stick on hundreds of little pieces of Zip tape.
Aside from the nail heads, the Zip tape WAS much faster to apply. I snagged a partial leftover roll, and have already found multiple uses for that aggressive tape (e.g. taping 12V DC whole house vacuum wire to the PVC vacuum lines).
I'm planning to use ZIP R-sheathing for a renovation and am trying to decide between tape and/or fluid-applied for this. So I appreciate all the good information in this thread. From what I've gathered, the main advantage of the Zip Tape is that it cost's less and goes on panel joints more quickly. But if the quality of the seal is the primary consideration (cost and time secondary) is it safe to say liquid applied is the way to go? It seems so but thought I would ask here in case anyone is still following this. I've also read liquid-applied is more fool-proof, which for a first timer would be an added plus. Thanks for any feedback on this.
Overall, the Zip fluid sounds like really amazing stuff!
These videos really seem to promote it as pretty amazing stuff:
https://www.youtube.com/watch?v=rSdb8cCOc6c
https://www.youtube.com/watch?v=Mn5KaKu-tt0
https://www.youtube.com/watch?v=CVAzMmgijGk
I wonder how much more it would cost vs. the tape on a typical house project?
Brent,
Thanks for the response and video links. Some of the those I had already seen, but the one on ZIP System 2.0 was new to me. The comments below the videos are interesting to read as well (some good information there).
The cost question can be tricky, because you have differences in material cost as well as differences in application time. If I were a builder and doing this a lot, I would probably look pretty carefully at that. In my case, the job is small enough that the cost difference is a non-issue. I mainly want something that will go on easily and seal well. Liquid flash looks like it will better meet my needs, I think.
I found both the tape and the liquid to be essential. I wouldn't start a Zip job without both on hand.
Matt, if you don't mind me asking, what were the situations where you found the tape better to use than the liquid?
My main concern with the tape (and this is an issue with tapes in general) is getting it to roll out smooth and wrinkle free while keeping it straight on the seam. But maybe ZIP tape is more forgiving than others I've worked with.
My framers didn't do what I'd call a great job with the zip tape, but it was good enough for me to go over with the roller and/or fix problems.
I found the tape superior with Z-flashings. I wouldn't even bother trying the liquid here or you'll get it it all over.
The stretch tape I preferred for my window sill flashings. That stuff is robust, and I think a better use of time and money than using the liquid flashing.
I also used the stretch tape on plumbing/conduit penetrations 1-3" diameter. The holes are generally bigger than you'd bother trying to flash with the liquid, plus they'll be jostled around and the tape can handle that well. I cut a hole in a square piece of the stretch tape, and slid the stub outs through it. It was a royal pain in the ass but it came out perfect so it was worth it in my opinion.
I used the tape on an interior OSB air barrier, with 3m 90 spray adhesive applied to the OSB first. The liquid would've been overkill here, and wouldn't have spanned some of the larger gaps like the tape did.
Thats all I can think of at the moment. If they were the same price I still don't think I'd use the liquid on all the sheathing seams either. If you follow up on that Zip 2.0 video, the builder didn't achieve any better air sealing by using the liquid everywhere. I'm glad he tested it.