basment leak from walls

Old 11-02-05, 02:17 PM
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basment leak from walls

Recently in my neighborhood,due to the heavy rain(for 8 days non stop) many basements were flooded, including mine. Water seems to have been entering thru a crack in the wall. I noticed water streaming out of a crack that looked like it was once coverd with a thick paint(assuming to prevent the leak) The wall that has the crack in it, is not directly connected to the out doors. Directly above that wall is a small mudroom.the basment is used mostly for a tv/play room and we do not plan on spending tons of money to fix it up but want a cheap yet helpful answer
My questions are as follows:
would a french drain have helped, if it was from the outside? A french drain can be installed either indoors or outdoors,no?
What can i do to the wall where the crack is? Is there some sort of sealer that can be applied from inside, to prevent water seepage,again?
Would i benefit from digging the perimiter of the home and sealing the outside walls,with tar or a sealent,to prevent seepage,as well?
Thank you or your help in advance.
Old 11-02-05, 04:05 PM
Join Date: Mar 2005
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basment leak from walls

You have a leak because of the level of the water in the soil outside the wall. Even though the wall area was protected by the mud room there was sufficient water pressure to leak at that point. There probably was water behind all of your walls, but you were lucky the leak was limited to one area. A basement with poor surface drainage around it is just like a swimming pool in reverse.

You first and most economical step to take if you want to prevent an occurance, is to make sure you have working gutters with drain extensions 8' to 10' long. The drainage around your home should be away from the house, not towards it (positive drainage).

From your description, the crack was covered with a product the identifies itself as a waterproofer. No paint or coating can truly waterproof a wall as you have seen. Those that are advertised as being penetrating obviously do not work as crack fillers. Coating are best described as moisture barriers, not waterproofers.

To answer your specific questions:

1. A french drain or drain tile is the most positive method to remove foundation water and prevent leakage. The drain tile can be installed either inside or outside of the wall footing. Some builders use both locations because of each has particular advantages.

2. Filling an existing crack (not another coat of "mystery paint") will help. You had a very rare rain event. The key to filling a small crack is cleanliness, dryness and pressure to force the sealant deeply into the crack. Larger cracks can be enlarged and filled with a hydraulic cement plug. Filling cracks is cheap and easy.

3. Digging and sealing the outside of the walls in not effective. If you are going to dig around the outside, you might as well install drain tile leading to a sump with a sump pump or drain it to "daylight" (outside away from the house). You alternately could install interior drain tile with a sump that also has the benefit of eliminating the water under the floor slab.

If you have lived in the house for a few years and this is the first leakage you have had you are not doing to bad if you don't have positive water control. Attention to the surface removal of water (downspouts & positive drainage) and collection and removal of groundwater (drain tile) are the most positive step you can take.

Good luck


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