Self-Adhered WRB and Sheathing Seams
Hi,
I tried posting this before and it seems it did not post, so I apologize if this is a duplicate post.
I am looking for some real world experience suggestions. We will be stripping the cedar channel siding and tar paper off a house that is on the beach in the Clearwater Beach area of Florida that has high humidity issues. Trying to make it as air tight as possible (not comfortable with a liquid applied wrap), I am trying to see what others are doing when they use a self adhered house wrap. We will probably be using the Vycor enV-S product. When I have looked a the Delta Vent SA, Hydro-Gap SA, Blueskin, Aluma Flash Plus, etc, I have seen they all suggest filling any plywood gaps that are greater than 1/4″. No problem.
They do differ on two different other application details.
1) Some manufacturers (Dorken, Aluma Flash Plus) say to tape or liquid membrane the plywood seams. Other manufacturers say that there is no reason as the self adhered WRB already does that (Benjamin Obdyke, GCP Vycor, Henry Blueskin).
2) Some (Dorken, Aluma Flash Plus) say to tape/seal with sealant the vertical and/or horizontal laps. Others (Benjamin Obdyke, GCP Vycor, Henry Blueskin) say there is no need as they are already stuck together via the overlap.
What is your experience?
Thanks,
Bob
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Replies
I've never done any seam sealing with self adhered, installed directly over the substrate. Make sure to plan your install out ahead of time around your windows and doors as it is easy to end up with reverse laps.
I guess if you do have a big gap (1/2" or so), I would fill it with gun foam and trim it flush, much easier and quicker than caulk.
Dan Kolbert, Ian Schwandt, and Mike Maines offer some tips based on real-world experience working with self-adhered WRBs in this article, although none talks about filling sheathing seams, just bridging them with the WRB.