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Window Installation advice

user-7061227 | Posted in General Questions on

My neighbor is building a house and I am pretty sure the windows are being flashed incorrectly. Could you please opine on the following pictures? The house wrap is BO hydro flash (not SA). Thanks

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  1. Expert Member


    The two big things I noticed (besides the shoddy workmanship):
    - The WRB should have been cut at the head so it could be lapped over the top flange once the window was in.
    - The bottom flange should not have been taped.

  2. Patrick_OSullivan | | #2

    Some of the photos make you think they were on the right track (like it appears there was some attempt at sill flashing with zip tape, but then others are problematic.

    It's surprising that they're using a premium WRB (HydroGap) and then executing details poorly.

    The window opening should be flashed. And then the window should be installed and the WRB lapped over the head. Sometimes the WRB will be folded into the opening to protect the sides of the window RO (instead of flashing it first), but the WRB needs to lap over the window head (and its flashing).

  3. user-7061227 | | #3

    Agree. no sloped sills, no back dams. the whole job is cringe. Spec home asking 3,800,000?!?!

    1. Patrick_OSullivan | | #4

      Sloped sills and back dams are basically never done, so I'm unsurprised they're missing here when the basic workmanship is as bad as it is.

      But honestly, the biggest surprise to me remains that they are using an expensive housewrap when, unlike the upgraded/expensive shingles, no one will ever see it.

      My guess is that it was on the drawing specifically by name and the builder had no choice. At least they made up for it by installing it poorly.

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