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Community and Q&A

Window Flashing

BPortnoy1 | Posted in General Questions on

Hello. We have Marvin windows in my new construction home. The siding is already up but looking back at photos it seems the flashing was done incorrect. They put the foil tape on the bottom which I know is not recommended as water that gets in has no where to go. I’m inclined to removed siding in these areas and remove the tape however  the contractors also did not install the specified furring strips for rain screen so I’m wondering where the water will drain out anyway if I remove flashing. Would
love advice.  I attached two photos. One before the flashing tape was applied and two after. Thank you!

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  1. Expert Member
    Michael Maines | | #1

    It's not incorrect; it's called the full barrier method and as long as the window never leaks it's fine. But some windows will eventually leak, so many of us prefer to allow the sill pan to drain. If you pull the tape off and loosen the nails in the bottom flange, you can probably slide popsicle sticks or bamboo skewers behind the flange. You don't need much space for water to drain.

  2. BPortnoy1 | | #2

    Thank you for the help. Good to know. This is from Marvin install guide. It actually looks like they don't want flashing on the top which I also have. Do you see any issue with that?

    1. Expert Member
      Michael Maines | | #3

      I believe they are showing the flange taped to the sheathing under the WRB flap. That allows water that gets behind the WRB to drain out. There are pros and cons to that approach. Some installation details are required for their warranty while others are suggestions.

      There is too much to know about installing windows to write here. This would be a good place to start:

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