aemeijers wrote in
:

Rob Kiz wrote:
I have a problem with horizontal and step cracking in my concrete
block basement walls. The step cracking looks relatively minor, but
there is a nasty looking horizontal crack most of the length of one
wall. It is close to a quarter inch wide in some places and located in
the fourth joint from the top which is about two blocks below the soil
line.

The cracks have never leaked. I did do a quick job of repairing the
largest crack two years ago but they recracked. I'm guessing from the
location this is due to freezing/thawing.The walls are slightly bowed
- if i am measuring properly, there is about a half inch of
displacement. I believe the displacement has increased only slightly
since 2002 when I had an expert evaluate my basement before i
installed a rec room. (The large crack was discovered at that time
under some wood paneling - that's why i called the foundation expert)

We are now getting the house ready for sale. I am considering having
the crack tuckpointed and disclosing the repair as well as the
existence of the crack behind the finised part of the basement. I am
pretty sure the cracks will reappear after the next freeze/thaw and I
do not want a future lawsuit. I'm going to have some contractors in
this week, and i'm wondering if they will try to talk me into steel
posts or excavating.

The walls without the large crack also show some displacement. Would
anyone know what amount of wall displacement is considered accepable?
Also, i get the geneal idea of determining displacement by dropping a
plumb and measuring distance to the wall. But at what levels would I
measure? The top, middle and very bottom measurements are all
different. Is it the greatest dufference?

Thanks in advance for your advice/opinions.

Rob

Purchased a house with a similar problem, horizontal cracking near the
midline about two feet down from the soil line. The first part of the fix
was to replace gutters and to insure that any potential water problems
were addressed. The second (and more painful) was to open the wall up at
four ft. intervals and to create a continuous reinforced concrete column.
(not as bad as it sounds) basically I had a civil engineer create a plan
for repair, documented to the local authority, stating the rebar size,
placement and frequency. He also specified the concrete mix and the
locations in the wall requiring the reinforcement. This ended up
requiring the four ft. intervals and 1/2" rebar continuous from top to
bottom.

The repair was done about four years ago and there has been no opening of
cracks or any leakage of water in that period of time. Total cost for
gutters and refit was around 5K using licensed contractors. (I wanted to
be sure that I could respond to any buyer concerns when selling the
house)

There are a couple of other strategies that can also be used in this
situation. The first is the one suggested above, excavate the outside and
pour a ground beam to direct the force of soil towards the corners after
installation of drains. The other is to epoxy carbon fiber strips on the
interior of the wall vertically. This places a tensile member with great
strength on the part of the wall to resist the thrust.

All of these solutions assume that you are addressing any water problems
by regrading the outside soil away from the house and/ or ensuring that
gutters are working properly and are discharging the water away from the
foundation.

Good luck with the fix.