Efflorescence under window sills


Old 05-25-17, 07:00 AM
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Efflorescence under window sills


After winter I noticed efflorescence on the bricks below 2 window sills.
Sill looks to be made of concrete if it matters.

Windows are brand new and properly caulked everywhere, installed last autumn.

Any ideas how water could penetrate there?


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Old 05-25-17, 07:40 AM
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What is the seal made of? could it be holding moisture and then releasing it below?
Old 05-25-17, 11:32 AM
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Was the concrete sill already there or was it new with the new windows? I'm thinking like mark that the concrete is holding moisture that seeps out slowly into the bricks.

Any signs of moisture above the window? How about a picture from farther back showing roof to ground?

It it turns out to be the concrete sill acting like a sponge there are concrete sealers that might help. The concrete pros mat comment if this is possible.


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