Strange situation in the basement of my house. The basement has had a known
water problem, the previous owner "fixed" it with a french drain on the
uphill side of the foundation and that did appear to halt water seepage.
After installing the french drain he covered the basement with wood
flooring, supported on 2x4's. I can only guess how long the flooring has
been there, 1980's possibly earlier, but right now I'm in the process of
ripping up the flooring. The concrete under it doesn't appear water
damaged, although the boards used in the flooring are well into a decayed
stage and dry rotted to heck and gone. So there is the history, during my
remodeling of the basement I leaned drywall sheets up against the foundation
walls to keep them out of the way. Anyway, I have begun to clean up the
area and noticed that in one spot there was moisture dripping on the
flooring, mold (the white fuzzy kind) on the concrete, and fresh signs of
efflorescence and moisture on the foundation - but only in the spot where
the drywall was touching the wall. There were also about a zillion angry
spiders too, one of 'um big enough to challenge me to an arm wrestling
match - I declined the challenge.

It was only in one spot, and only where the drywall was leaning against the
concrete. Was the drywall attracting water through the concrete, or is this
a completely coincidental situation. I can deal with a water problem, I
suspect it exists regardless of this particular occurance, but I wanted to
be sure of the cause. I want to add, that the flooring where the water was
seeping through prior to this had NO signs of water damage. So whatever the
cause its new and not something that has shown in 30 years. Unless of
course the drywall was acting as a drip path for the seepage, whereas
normally the water would drip down the wall and pool under the flooring.