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Spray foam sill plate on the outside of wall

eli2020 | Posted in General Questions on

I’m having a home built and the framers failed to install seal sealer under the outside wall sill plate. I’m talking about the pink foam matting, but the sill plate is pressure treated lumber. This is a slab home with brick around most of the house. The builder decided to use great stuff gap and crack to attempt spraying between the concrete and sill plate, on the outside. The foam also gets down to the brick shelf, which is one of my concerns. I have a high sensitivity to mold and concerned about what issues this might create. The brick shelf is a few inches above ground. This is a humid climate in Louisiana and a high water table. Has anyone ever seen this done and/or have any recommendations. There was an attempt to cut back some of the foam off the brick shelf. However, there is still some touching the brick shelf.

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  1. user-2310254 | | #1

    I'll give your post a bump. Personally, I would scrape off the excess foam to be on the safe side. I'd also use one of the special purpose tapes to cover the gap between the bottom of the sheathing and the brickledge.

    A similar issues was discuss in this thread ( It might be helpful here.

  2. bigred | | #2

    I agree with Steve, about scraping the foam, but I'd use a liquid flashing, zip, polywall, proseco etc to seal the sheathing to brick ledge. I don't think tapes will work as well here as a liquid flashing

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