Taped Zipwall or sheathing with Ice & Water Shield on a REMOTE/PERSIST roof?
So any thoughts on what is better or more practical?
I’m getting ready to start sheathing a roof (which will have all of it’s insulation outboard of the WRB and sheathing, with a cold roof on top). It is a R-66 EPS roof.
On one part of the project (a separate building, same construction technique (REMOTE/PERSIST), we used barnboard, then 1/4″ plywood (to hide the ice & water shield above it) from showing through any knots or such from below (exposed cathedral ceiling), then R-66 of EPS above, with 2×4 furring and then plywood and then metal roof.
On the first building we used Prosoco R-guard system on the exterior walls, doors and windows. Prosoco makes a fantastic product, but the MVP and Joint & Seam Filler was just too labor intensive to apply and finicky to get consistently just right. With that said though – I LOVED using the FastFlash and Airdam products for the windows and doors. It has done such a great job, so……..
On the second building in this project we decided to use the Zipwall 7/16″ sheathing on the exterior walls. I am certainly glad I did! I’m so impressed with the Zipwall/Huber products. The Zipwall tape is AMAZING. I can’t believe I haven’t used the Zipwall previously. We will be constructing the roof the same way as the first building, but because I’m so impressed with the Zipwall, and with colder weather on the way, I thought to just use the Zipwall 7/16″ sheathing (taped obviously) over the barnboard and not worry about ICE & Water shield over the Zipwall (except at the valleys and eaves).
I know the Zipwall is supposedly waterproof, and it has performed well, but a good ICE & Water Shield will truly protect the roof. I’m not worried about covering up the whole roof in ICE & Water shield, because of the REMOTE/PERSIST strategy. If I went the way of ICE & Water shield, I could just use OSB or 1/4 plywood over the barnboard again.
Zipwall is twice the cost of OSB, but it has the WRB already on it, which as I mentioned earlier is performing excellently. The Zipwall route ends up being about break even, after the ZIpwall tape, when compared to OSB with ICE & Water.
Any thoughts, or wise advice?
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