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Community and Q&A

Preferred window/door sill flashing tape?

GreyWolf92 | Posted in General Questions on

I’ve been looking for some water-proof/vapor closed window sill tape alternatives to the pro clima extoseal.

Planning on using vapor permeable tape for pretty much every other application but I’ve been told it’s best practice to use a vapor closed tape at the window sill because this is the one place where water may sit for longer periods.

What is your guys preferred tape for this application?

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  1. Expert Member


    I've never found much difference between any of the brands I've used. Right now I get Resisto or Henry Blueskin depending on what's in the lumberyard.

  2. GreyWolf92 | | #2

    Hi Malcom. Are either of these vapor closed? The bottom window sill potentially is the most important so I want to make sure I use the best.

  3. Expert Member

    They are both Peel-and-stick membranes. Great for creating sill pans. They don't stretch around corners though, like Dupont's Flex-wrap, so you have to use three pieces and bow ties.

  4. GreyWolf92 | | #4

    Great thank you! Have you ever used Pro Clima extoseal or Du-point flex wrap?

  5. Expert Member

    I've used Dupont flex-wrap. I find it quite hard to get the wrinkles out, and it doesn't feel as robust as the Blueskin - although that is only my impression.

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