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Community and Q&A

Effloresence on concrete ceiling

RSBme | Posted in GBA Pro Help on

Hello. I have a client with a basement that has a concrete ceiling section about 10’x35′. There is a brick walkway above it and it has leaked into the basement cieling causing efflorescence and that drops all over what they have stored in the basement.
Though someone sprayed Moxie on the exterior surface of the bricks, client reports they still have leaks in basement cieling that cause lines of efflorescence, which, again, falls on their pocessions stored below.
They have called me to try and at least stop the efflorescence from falling off the cieling. While it would be great if there was a cementitious product that adheres to cieling that stops the moisture AND the efflorescence, I would still be fulfilling my job if it, for now, just stopped the efflorescence (I know the two are much linked in cause and effect).
I do not know if anyone sprayed Moxie on cieling of basement or not.
Any suggestions for possible solutions/products?
Thank you much for the knowledgeable help.

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  1. User avatar GBA Editor
    Martin Holladay | | #1

    I'm not familiar with Moxie. After some Googling, I discovered that it is a brand of concrete waterproofing -- actually a family of products.

    If you are describing a basement without a house on top -- a basement with a concrete ceiling that is unprotected from the weather -- it's never going to work. That's because concrete isn't roofing.

    If you want a roof, you need to install roofing. Generally you would need to remove the brick walkway, expose the concrete slab, and install some type of membrane roofing like EPDM. You would also need flashing at the intersection of this concrete slab and the house that it's near.

    Once you install your roofing, you can install pavers over the roofing if you want to walk on top of the roof.

    Without roofing, it's no surprise that your roof leaks.

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