Zip system with overdriven fasteners
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We are using Zip R6 insulated sheathing for a WRB and airbarrier. The framing is now completed, and most of the nails are countersunk by 1/4″, compromising the treated surface of the Zip.
I am told that the sheathing will still pass code, and that Zip’s warranty still holds. Okay, I believe that.
But: would a high-performance builder tape over the nailheads – or caulk them – just to be safe?
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Replies
Mark,
You can seal them with Zip Liquid Flash.
https://youtu.be/Mn5KaKu-tt0
I think it's good practice to cover the fastners in a WRB regardless. Most people would roll their eyes, but hey, I'm OCD.
I prefer a liquid flashing just cause it's a little easier to work with, and more efficient with uasage and wastage.
+1 on the liquid flash.
Now would a high performance builder take the time to do that? If it's not needed to be done in order to pass inspection or maintain warranty than I would think he's not obligated to do it.
I'm not sure just because poor workmanship will pass inspection that gives a builder an out not to remediate. Over-driven nails affect both the ability to withstand moisture and resist shear.
Mark,
To see a project utilizing Zip liquid flash, Google search ‘Matt Risinger Zip 2.0’. That search will bring up the YouTube video of Matt’s interview with Doug Cameron. If you are not yet familiar with Matt’s videos, then you are in for a treat.
To protect the smart investment you made in Zip R sheathing, you should definitely include a rain screen detail. Zip R with a rain screen detail is what I’ve settled on for the design of my upcoming build. That project has been purposeful delayed for coming on two years, over which time I’ve carefully followed GBA and all of the great leads and links offered in blogs and Q&A posts.
Regards,
Aaron
Thanks, gentlemen. :-)
Liquid flash sounds like the answer.
And, yes, Aaron, I am planning on a rainscreen.
Mark
Hi Mark -
Here is the official response to this issue from the Technical Library Huber online: http://www.huberwood.com/technical-library//8/323
"Do Fastener Heads Need to Be Taped Over?
Overdriven fasteners do not necessarily void the ZIP System® sheathing warranty. However, when a fastener misses the framing and results in a “shiner” or if a fastener penetrates roughly half way or more through the panel, steps must be taken to seal these penetrations. Shiners should be removed and holes should be covered with ZIP System™ tape or ZIP System™ liquid flash. Fasteners that penetrate roughly half way or more through the panel should also be covered with tape or liquid flash."
I have seen the lab and field tests that Huber does on their ZIP sheathing products - really impressive robust tests and results, both in terms of water and air leakage when fasteners are overdriven "slightly" (less than the halfway overdriven that need tape or sealant).
On the other hand, it certainly does not hurt to seal any and all penetrations with the Liquid Flash sealant.
Mark,
We just had this same over driven fastener situation with our R-6 Zip Sheathing a couple of months ago. We ended up sealing every single nail head with liquid flashing. Sealing those nail heads with Zip Tape would have been a TREMENDOUS amount of additional work and time. I can't imagine being on top of a 24' ladder and dealing with hundreds of little pieces of sticky Zip Tape. With a sausage caulk gun and a putty knife, the job goes pretty quickly.
If you are in a seismic hurricane or tornado zone, I would ask for Steel Wall Bracing to be installed on the inside of the wall or a letter from a licensed engineer stating that the wall is sound in their opinion. Does anyone else find it strange that Huber made no commit about the structural question?
https://www.homedepot.com/p/Simpson-Strong-Tie-TWB12-11-ft-4-in-Galvanized-Steel-Wall-Bracing-TWB12/100375133
Walta
Like other have said, use the liquid flash. I used Prosoco because I had a free case and just by chance, the color matched my 1/2" Zip wall sheathing. I decided to use the 1/2" because I was concerned about overdriven nails and like the extra depth to help compensate. Framers love to overdrive nails.
Jonathan,
Yes they do! Although the most common cause I see when doing inspections is owners using compressors with too small tanks that have to cycle frequently, leaving some nails a bit proud, and some overdriven.