Photo of moisture on concrete floor in slide show
GBA Editor
| Posted in Webinar Follow-up Q&A on
what’s the origin of the moisture in the concrete floor and mold behind the trim photo? Was it when the floor was cleaned? Or a plumbing break? Or when the concrete was drying during install?
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This slide was an example of wicking--moisture moving by capillary action up through the concrete and wood and into the gypsum board (all porous). The floor is not "wet"--it looks "dry" but without a capillary break between these materials, moisture continually migrates from the concrete. It is likely that there is no capillary break between the soil and the concrete, so there is a continual source of moisture.