dk wrote:
My 82 year mother lives in a house where the floor is sinking in one
corner of the house. The basement floor is cracked and sinking along
the outer walls. The house walls and ceiling are plastered and I'm
afraid that the ceiling is going to come down.

I know there are many companies that claim they can correct the problem
and I'm a little leery.Any ideas as to the best way to correct the
problem and the cost associated with correcting the problem.

Thanks
David Kight

I had a similar problem. It turned out that when houses here were
built, they used construction sand to bring the lot up to grade. Over
that, they put dirt, then grass. Below the sand, the grade went
downhill toward our house. So, when it rained, the water that seeped
through the grass and the dirt was carried by the sand toward our house.
The lady who had our house before apparently left because of the
problems that caused. For starters, the rear deck was sinking. This is
a very long story, so I'll start with the punch line and go toward the
details so you can skip as you wish:

The pros recommended a french drain. They had even put one in under the
deck in back, but they didn't put a sock on it, so over the years it
filled with sand, etc. When I dug it up, it weighed a ton! Now they
wanted me to put one in on the side of the house where the water was
coming from. My research showed that a french drain is about 24 in.
deep, filled with stone, uses a slotted 4" pipe and should be covered
with a sock to help keep out debris. I would need 25-50 ft. I heard
estimates of up to $1200 for it.

Bottom line: what I found showed that the problem was at about 48"
below the surface and deeper, so the "french drain" they proposed would
have meant the $1200 spent for it would be better off as a gift to the
poor. So much for the "pros"--engineers, architects, etc. Long live DIY!

What I did: Based on test digs, I found the water level to be four feet
down. The house is about 1930 and has a crawl space. The footings went
down no more than four feet. So, I wanted to provide protection down to
six feet to keep the water flow away from the footings and the deck.
So, I dug a trench six feet deep. I lined the downhill side of the
trench with 6-mil vinyl and put a socked slotted 4" pipe at the bottom.
It goes to a non-slotted 4" pipe which empties in the street (with
permission of the city).

The results: The soupy stuff under the deck is now dry. After rains,
it dries right away. The pipe that goes to the street tells the whole
story: after a particularly heavy rain (which we get a lot here in
South Alabama) water will come out the pipe to the street for 3-5 days.
I shudder to think that this water could have all collected under my
house!

How I found out what my problem was: The first clue was the soupy stuff
under the deck. It was supposed to be just sand. Secondly, there is a
small basement which had been used for laundry. The floor always had a
couple of inches of water. They had put a pipe in the wall to carry it
out, but they didn't put it like a drain in the floor, so it only
drained off the excess. She apparently did the laundry standing on
plywood on top of concrete blocks. The floor of the room was slimey.
(She later added a small addition to the house with a laundry room and a
second bathroom.)

Also, the dirt in the crawl space was mud, not dirt. There were swirls
that showed that liquid flowed through, carrying the dirt. In the
house, the floors were uneven. The floors went downhill, toward the
rear of the house. No wonder the house was so reasonable!

I did a test dig by the small basement, which was formed with concrete
blocks. I found the exterior of the blocks were obviously pourous. So
I dug to below the concrete flooring, pressure washed the concrete
blocks and painted them with elastomeric (however you spell it) paint,
which basicly coats it with rubber. Then I put a sheet of 6-mil vinyl,
covering the surface. Other than the small basement, the rest of the
underside of the house is crawl space. They had filled in the sides,
but when I checked the side where the water ran downhill (slightly,
anyway) toward the house, I removed a huge ancient azalea root and found
a big hole where the water apparently flowed in and then through the
crawl space. I also found that tree roots from the neighbor's tree had
pushed through the crawlspace wall and had made holes where water could
come in.

I waterproofed the entire foundation. But when I came to the corner of
the house where the lady before us put in an addition, before I got to
the bottom of that footing, water came up. Uh, oh, I thought. I dug
another 4 ft. hole around the corner, uphill, and found water there at
about 4 ft. I dug two more 4 ft. holes along the neighbor's fence. I
could see the slope of the underground water. It was obvious that I had
better get it fixed or the addition was going to start caving in.

So, as I said, I dug a 50ft X 2ft X 6ft trench, lined the downhill side
with vinyl and put a socked slotted 4ft. pipe at the bottom, draining to
the street. Yes, I dug it (I'm 73). I looked at a trencher, but it
would only go down 4 ft. Nation's Rent wanted nearly $500 for a backhoe
for a day, but (1) I didn't know if I could get it done in a day, (2)
there is a sewer line from the neighbor's in the middle of the trench
area, and (3) the area between the house and the neighbor's fence wasn't
enough to pile six feet of dug up dirt. So, I had to do it by hand.

The neighbor's tree had roots that went through the area of the trench
(and through the crawl space wall). Today that tree has a lot of
branches with dead limbs. I wonder why.

In digging the trench, I saw that there was up to a foot of dirt at the
top, and construction sand the rest of the way down; thus, my conclusion
that they used the sand for fill to bring the lot up to grade. I tested
with a moisture meter and found the dirt had a couple of points of
moisture, but the sand had none. Since it hadn't currently been
raining, that was understandable, but the point I got was that whatever
water there was, had gone somewhere else--under my house, probably. The
dirt collected the moisture, but the sand did not.

Fortunately, I dug it in a dry period. When I got to the bottom, the
walls began caving in due to the residual water in the ground. I had to
act fast. Since I dug the trench 24" wide, I dug the last foot or two
just wide enough for the pipe, so I could stand on the higher part and
scoop out the wet material from the pipe hole fast enough to get the
pipe laid.

I put in a solid 4ft. pipe at the back of the property to carry the
water to the street (I have a corner lot). Connected to it is the
socked pipe from the trench, two downspout runs, and a new drain for the
basement.

The result is that today the basement, formerly slimey, with boards on
concrete blocks to walk on, is now bone dry. I mean bone dry. The
slime under the deck is now loose sand, which blows in the wind. The
dirt in the crawlspace is now dry (I put exhaust fans in for a while).
I formerly had to cut room for the basement door to open under the deck
because the deck was sinking, but I haven't done that for a long time now.

If I had someone do the project (architect, engineer, etc.), they
probably wouldn't have done it right, and the cost would have been
somewhere between $5,000 and $15,000. I probably spent $500 for paint,
pipes, and special tools. DIY wins again.

John