I am refinishing basement. In one side of the basement there is a 2" hole drilled in the wall near the floor. From the hole along the wall there is shallow channel in concrete floor going to the sump pump pit. I talked to a waterproofing contractor and he said that the hole had been drilled to released water pressure from outside the foundation and let water come inside the house and run through the channel to the sump pump. For year the I have been living in the house I saw only once water coming through the hole.

Now my question. Unfortunately, the channel is very shallow, uneven and too wide, it's done ugly. I don't know how to box it or fix stud to the floor over it when framing the wall. What should I do to make it better and be able to frame the wall? I thought of making with electric hummer a groove in concrete floor along the wall where the channel currently is and burying a plastic hose running from the hole to the sump pump pit. The hose would run parallel to the wall 1" from the wall. The hose would be under the floor surface so I can easily put a frame stud over it. Is my idea suitable or not? I have basically two concerns. The first is can I damage the structure or foundation if I start using heavy hummer to break concrete floor for the channel close (1") to the wall? The second is how to clean the berried plastic hose of something (dirt or stones) will block it? Also what diameter should I use for the hose? Do I need to maintain a slope in the hose from the hole to the sump pump pit?

 

agalkin,

The best way of keeping liquid water away from a foundation is to divert downspouts away from the house, and slope the ground away from the house. In that way any rain, snow melt, etc. will not drain down into the soil near the foundation. For any water that does drain down into the soil near the foundation, and also for any excessive ground water already in the soil from a high water table, a perimeter drain tile and stone or gravel backfill has been the standard approach. This is a waterproofing system. The same application is done to the "interior" of the lower level and this works extremely well especially in older homers when exterior applications cannot be done.
When liquid water gets into such a gravel backfill, it quickly runs down into the drain tile and is diverted away through a pipe either by gravity or a sump pump. When a drain tile is used, but soil is used for backfill, the water can't drain away as quickly, so it tries to drain through the foundation wall. If enough liquid water is present, hydrostatic pressure will force it through any opening it can find in the foundation wall, no matter how small.
The purpose of the stone or gravel backfill is to relieve the hydrostatic pressure. With the correct backfill material, the liquid water will travel the path of least resistance: through the backfill into the drain tile, rather than through the foundation wall. I will point out that drain tile comes in two styles - rigid and flexible. The rigid has a slot on one side and this is installed with slot down. The flexible has slots on 4 or 6 sides, if you will but this should be installed with a silt sock over it. Costs more but prevents silt from getting into the pipe. Most homes, for interior applications use the flexible but either is acceptable.
When the soil is merely damp, as it often is, liquid water isn't the problem. When damp soil is next to a foundation, it will cause the foundation to get damp. The dampness will work its way through the foundation wall and eventually enter the basement or crawl space. Concrete and masonry are actually very porous, so dampness can move through such materials fairly easily. (This is done through a process called capillary action.) Once the dampness reaches the interior surface, it can evaporate into the basement or crawl space, increasing the moisture in the air.
To stop the dampness is relatively easy because, by not being in liquid form, there is no hydrostatic pressure. A simple foundation coating will do the job. This coating is called dampproofing. It isn't a substitute for waterproofing.

PROCESS: Remove about 16" space out from wall. Ensure that you are about 8 inches out from footing. Dig a trench along the footing that slopes gradually towards a sump basin. Trench approaches the sump basin from two sides. Drill ¾" holes into each of the block cavities (2 per block) in the course of blocks that sits directly on top of the footing. Water now comes out of these holes when it rains. Place 4" corrugated drain pipe in the trench and run this all along the trench to the sump basket. You may use a silt cover or a silt sock which covers this pipe of which then you would place 3/4" pea gravel over this to a level that leaves about 4" of space for your new concrete. Place the concrete all the way to wall - NO SPACE IS REQUIRED. Install a good sump pump and PVC piping - 1 1/2" out to the exterior and away from the homw for proper drainage. This could be buried and run into a drywell at least 20 plus feet away from the home on down grade.

Hope this helps!

 

Thank you very much for your details response. However, I have several questions. First of all I am less concern now with basement waterproofing. I read multiple times that the major effort in basement waterproofing should be in improving proper drainage system outside the house. From my conversation with waterproofing contractor I understood that the hole drilled in the basement wall is necessary and I can't just patch it. So my primary concern now how to make the water channel that is currently uneven, too shallow and poorly built better and suitable to finished basement. From you PROCESS section it was unclear to me where (inside or outside) the house I nee to create a trench and how it moves to sump pump that is inside the house. I would be very thankful to you if you could explain to me in somewhat simpler way your suggestion. Also do you have any Web links to the system you are describing with maybe some drawings.

 

agalkin,

Drain tile would be placed inside. I have attached links to help with this so you can eliminate the eyesore that you have now.

http://www.dspinspections.com/basementwater.htm

http://www.binkleyandober.com/residential.php3

http://www.usinspect.com/Crawlspace/PerforatedPipe.asp

Hope this helps!