There is 3 feet of slab emerging behind my 80 year old garage. It has a 1/2" joint filled with tar (see photo). The joint runs under the back wall (cinder block) into the garage. I've dug out about half of the tar in the photo below. The leak appears to be at the top where the joint meets the masonry. At that point I can stick a screw driver most of the way through into the garage. The screw driver comes out with dirt on it. (The slab was covered with soil and dirt does come through with the leaking water). Any advice on how to seal this would be appreciated.

On Jul 18, 11:56*pm, brettismyname
wrote:
There is 3 feet of slab emerging behind my 80 year old garage. It has a
1/2" joint filled with tar (see photo). The joint runs under the back
wall (cinder block) into the garage. I've dug out about half of the tar
in the photo below. The leak appears to be at the top where the joint
meets the masonry. At that point I can stick a screw driver most of the
way through into the garage. The screw driver comes out with dirt on it.
(The slab was covered with soil and dirt does come through with the
leaking water). *Any advice on how to seal this would be appreciated.

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brettismyname

Run a garden hose gently against the upper back wall to simulate a
rainstorm and see what happens. Filling the crack with more tar won't
help if the rain gets into the crack further away from the garage and
travels along the crack under the tar and then comes up inside the
garage. Does the inside garage wall get damp or does water come up
from the crack further inside the garage and then spread out?

On Jul 19, 12:56*am, brettismyname
wrote:
There is 3 feet of slab emerging behind my 80 year old garage. It has a
1/2" joint filled with tar (see photo). The joint runs under the back
wall (cinder block) into the garage. I've dug out about half of the tar
in the photo below. The leak appears to be at the top where the joint
meets the masonry. At that point I can stick a screw driver most of the
way through into the garage. The screw driver comes out with dirt on it.
(The slab was covered with soil and dirt does come through with the
leaking water). *Any advice on how to seal this would be appreciated.

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|Filename: leaking concrete joint.jpg * * * * * * * * * * * * * * * |
|Download:http://www.diybanter.com/attachment.php?attachmentid=6580|
+-------------------------------------------------------------------+

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brettismyname

Sealing concrete and masonry form the inside is a near impossible
task. It's always better to start by trying to divert the water away
from the problem area. Add gutters if you do not have them. Extend
the downspouts further away from the house. 10 feet or more if
possible. Regrade so you have a slope away from the problem area.
Examine the general area outside and see if you can divert runoff at
other points in the property so that the ground around the structure
does not get so saturated.

[QUOTE

Run a garden hose gently against the upper back wall to simulate a
rainstorm and see what happens. Filling the crack with more tar won't
help if the rain gets into the crack further away from the garage and
travels along the crack under the tar and then comes up inside the
garage. Does the inside garage wall get damp or does water come up
from the crack further inside the garage and then spread out?[/quote]

Thanks. The water comes in the back wall along the top of the slab expansion joint that runs perpendicularly under the back wall (shown on photo). A silty bit of mud has accumulated on the inside where the expansion joint emerges from under the back wall. I have never seen water on the walls. Today I sprayed water from the outside to clean out the hole. After drying I am planning to fill the hole on the outside with a concrete sealant. Then I am planning to dig french drains around the perimeter to keep water away from the garage.

Sealing concrete and masonry form the inside is a near impossible
task. It's always better to start by trying to divert the water away
from the problem area. Add gutters if you do not have them. Extend
the downspouts further away from the house. 10 feet or more if
possible. Regrade so you have a slope away from the problem area.
Examine the general area outside and see if you can divert runoff at
other points in the property so that the ground around the structure
does not get so saturated.[/quote]

Thanks. please see my previous reply.

On Thursday, July 19, 2012 12:56:25 AM UTC-4, brettismyname wrote:
There is 3 feet of slab emerging behind my 80 year old garage. It has a
1/2" joint filled with tar (see photo). The joint runs under the back
wall (cinder block) into the garage. I've dug out about half of the tar
in the photo below. The leak appears to be at the top where the joint
meets the masonry. At that point I can stick a screw driver most of the
way through into the garage. The screw driver comes out with dirt on it.
(The slab was covered with soil and dirt does come through with the
leaking water). Any advice on how to seal this would be appreciated.


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|Filename: leaking concrete joint.jpg |
|Download: http://www.diybanter.com/attachment.php?attachmentid=6580|
+-------------------------------------------------------------------+



--
brettismyname

outdoor french drains are often ineffective unless they are below footer level......

so install shallow ones outdoors, regrade yard, repair gutters, move downspout drains far from house, then once that all fails jackhammer up interior floor and install interior french drains and a sump pump.

i did all of that spent 8 grand and all summer, i was the laborer on exterior work.....

the yard looked great, but the basement was still flooding

the interior french drain actually fixed it......

for 3500 bucks, no work other than to sign check, i just watchedb the pros do their thing, whole job took about 1.5 days

my exterior work took the entire summer of back breaing work including a new lawn...... sidewalks, plantings etc etc etc....