wrote in message
oups.com...
So, our house is about 6 weeks old now (new construction - we closed
at the of May), and we're having some rather severe problems in our
basement.

While it has been raining seemingly every day now for the past month
here in Atlanta, we've been to the basements of other houses still
under construction in the same subdivision and none of them have
the problem we're having, so it's just our house.

And the problem is, we're seeing water on the basement floor. It's
worst after a heavy rain, of course, but regardless we get wet floors.
It's mostly just at the base of two of the walls, and in one corner
the water actually pools up, though mostly its just dampness on the
floor along the walls. The floor at the middle of the basement is
dry as a bone - it's just where the wall meets the floor, coming out
maybe 2 or 3 inches from the wall.

There's no dampness on the walls, mind you, JUST the floors.

There are no visible cracks anywhere in the floor.

I have a weather gauge down there that showed the humidity at 80%
at one point. The builder came and put a dehumidifier in the
basement, but after a week of running 24/7, the humidity is down
to just 72%.

About a week ago we saw (yellow) mold growing on stuff we had
stashed down there, so we've spent the past week trying to clean
up what we could and tossing the rest.

The foundation has the black stuff (tar?) on the outside, and like
I said, it's not coming in via the walls anyways. The windows and
door are sealed correctly, so that's not the source of the problem,
and anyways the areas most affected are those furthest away from
the windows and door.

The grading on the house appears ok, although I don't have
instruments to measure it - I'm just eyeballing it.

The downspouts were just the standard ones that didn't have any
extensions on them, but after we complained the first time the
builder added some piping to the downspouts so they emptied out
about four feet from the foundation. It appears that did little
to nothing about this problem.

The builder also ran a snake through the foundation drain (which
yes, it is exposed to the surface at both ends) and there was
nothing clogging the drain.

We've checked all around on the second floor ceilings for leaks
and there's nothing visible. Nothing visible in the attic either,
so there's no *obvious* leakage coming in from the top of the
house.

The builder doesn't have any more ideas (at least not that he's
sharing with us), and we certainly don't know what else could
be the problem, unless there just so happens to be a spring under
our foundation (I know one guy to whom that actually happened!).

While it's tempting to just throw down a sealant on the basement
floor and forget about it, that only keeps the water from getting
to the top of the basement slab, it doesn't stop it from
permeating the entire rest of the slab just short of the surface.

If it's water table you're going to need a sump pump and drain tiles,
preferably on the outside. but if need be, on the inside along the walls.
If it's ground water that is draining down along the outside of the
foundation then it's got to be graded away. Can you dig a hole down to the
depth of your foundation--if so, you won't have any problem determining if
you have a high water table. If it's water table the last thing you want to
do is to try and seal it--the water is going to get in and if it doesn't,
worst case, your floor will crack. I've seen a crack right down the center
of the floor. It's a bummer and too bad you didn't see this before you
closed on the house.
MLD