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Belts & Suspender window install with Zip—install 2nd WRB before or after window install?

rocket190 | Posted in General Questions on

Hi, 

I’m trying to plan for the most resilient window method installation possible, and I’m looking for a tried and true Zip window install. This will be for climate Zone 6B.

Particulars of the build:

1. 2×8 framed exterior walls
2. Zip 7/16 exterior sheathing
3. Enerlux triple pane fiberglass windows with nailing flange
4. Siding will be 26 gauge steel in board and batten profile

My current plan is to install 3/8” lap siding for a sloped rough opening, and then seal and flash the rough opening per AAMA method B.  Then I would install the windows with thick sealing bead on the sides and top of the nailing flange, and then butter additional sealant around the nail flange making sure the flange sides and top are fully covered. 

The windows would stay in this condition for a few months to allow for all rough ins to be installed and then I would install new bumpy WRB (Tamlynwrap 1.5 ) before exterior siding installation. The second WRB will allow me to properly shingle window drip caps, masonry top flashing, etc. 

Does this sound like a bulletproof install? Any other recommendations?

I’ve seen some videos advocating for a thick bead of sealant on all sides of the opening, including the bottom. Doing this would kind of defeat the purpose of the slopes rough opening, but I can also see why it might make sense…

 

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Replies

  1. andy_ | | #1

    Why the second WRB?

    1. rocket190 | | #2

      I’m not worried about the large expanses, but a little bit nervous about relying on tape at window heads, and where I am switching from masonry wainscot to lap siding. For a relatively small investment it seems like cheap insurance.

      I chose Zip sheathing to create an airtight shell and to get me through a winter build.

      1. Malcolm_Taylor | | #3

        rocket190,

        It's also another way of gaining a small rain-screen gap.

        Just don't caulk your bottom flanges.

      2. andy_ | | #7

        If you're not worried about the large expanses, then I'd skip the extra WRB. Use an appropriate tape over the window flanges and for where the flashing meets the Zip. For where you'd like a rainscreen, I'd use a rainscreen and not rely on a crinkle that might or might not also act like a rainscreen.

        1. Malcolm_Taylor | | #8

          andy,

          That does sound like a more resilient wall to me too.

  2. Patrick_OSullivan | | #4

    I find gooey stuff behind and around window flanges to be reminiscent of elementary school art projects which end up with everyone messy and no one happy.

    Others may disagree, but I see no reason to put goop behind a window flange, nor over it. Tapes are much more predictable.

    1. Malcolm_Taylor | | #5

      Patrick,

      I tend to agree.

    2. rocket190 | | #6

      It would be nice to avoid this mess, but I believe sealant is needed to obtain warranty coverage for most windows.

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