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Crust issue on basement/garage drywall?

Michael Schonlau | Posted in General Questions on

I have a wall between my basement laundry room and the garage. This is a frame wall with drywall on both sides and fiberglass batts in between. I’ve noticed some crust white material near the bottom of the interior wall (see photo). Any ideas what might be causing this? There is no moisture damage apparent.

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  1. GBA Editor
    Martin Holladay | | #1

    That is efflorescence -- evidence that the bottom of your drywall was wet in the past. When the moisture evaporated, the dissolved salts (minerals) that were present in the water were left behind. That's what you're seeing.

    Is there poly under the slab? Has the area ever experience minor flooding or a damp floor situation?

  2. Michael Schonlau | | #2

    There was an incident of some standing water on the floor near that area. There is no poly under the slab - this home was built in 1973.

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