# Sealing pipe penetration



## Daniel Michael (May 26, 2013)

I have a water pipe underground that enters through the basement wall that leaks around the pipe when it rains. The leak stops sometimes once the ground is saturated. Foam sealant was originally used. I have dug down to the pipe and am seeking the best diy method to fix. After much web searching I may do foam again around the pipe, fill in dimple with hydraulic cement, then roofing cement, 6 mil plastic, roofing cement again, and another 6 mil plastic. Now, I wonder if I should fill hole with the clay soil, sand, or gravel to facilitate drainage?


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## jwal10 (Jun 5, 2010)

Clay soil, sloped away from foundation. Unless there is a drain pipe around the foundation, then refill with the same as was used. Me, I would use non shrink grout, it is what we used for all penetrations at the water treatment plant and vaults. Fill the void and then 3 thin layers, inside and outside, cone it out close to the pipe (thicker at pipe, tapering out onto wall, applied like drywall mud....James


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## wharton (Oct 9, 2011)

You are probably overdoing it with all the foam, and tar layers. I was a builder for decades, and found that leaks from this area are pretty uncommon. The reason is that most well drillers and plumbers drill a hole through the wall, then pack the pipe with hydraulic cement. The reason you have a leak is that the foam is neither ridged, nor flexible enough to do the job properly. As the ground settled, the pipe shifted and the foam could not maintain the seal. Hydro cement will create a permanent, tight seal. Clean the old opening out, wet it until it's damp, and pack cement in tightly with a margin trowel. I have permanently stopped flowing water through holes in a concrete foundation with this stuff.


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## Daniel Michael (May 26, 2013)

From my web searching these leaks are very common and also very common for hydraulic cement to eventually fail.


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## paqcrewmama (Oct 6, 2012)

Got the same issue at the cabin but that issue isn't quite at the top of the list yet. The hole in our basement seems to be from a discontinued pipe from the older well. It's down about 5 ft from the surface. Can it just be sealed from one side or do you absolutely have to dig down to to access both sides to seal?


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## wharton (Oct 9, 2011)

Daniel Michael said:


> From my web searching these leaks are very common and also very common for hydraulic cement to eventually fail.


 In thirty years I have repaired exactly one, and it was a slow weep. As for hydro cement failing, I'm quite skeptical of that claim. Most failure of products like this is directly attributable to user error. Clean fresh powder, proper mixing, a clean damp surface to apply to, and it will be working well long after you and I are gone. 

A "web search" of this problem probably misses the two real issues. First the product being dismissed as failing is probably plain old mortar, which is pretty indistinguishable from hydraulic cement to the average homeowner. Second, mortar used in this application will typically fail, since a successful mortar patch is tough to do. The area needs to be clean and nearly wet, and the area needs to be rewetted for several days to prevent the substrate from sucking all the moisture out of the mortar, until it has a chance to cure. Patching a dry dirty masonry wall with mortar is just a waste of time.

The OP is doing his "due diligence" in searching for answers to the problem. Unfortunately, this results in a common problem when attempting to help on a DIY forum. That being, too many homeowners tend to over research and falsely reach the conclusion that the best way to kill an ant is to use a shotgun. In his case, a quick, inexpensive, repacking of the penetration, using hydraulic cement will resolve the issue. The other issues that might need to be addressed is proper slope of the exterior grade at the area of the leak, and addressing gutters and storm water management surrounding the house. Other ideas like multiple seals of tar and poly, or attempting to backfill a limited area with a more suitable fill, are probably a waste of time and money.


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## 1shotwade (Jul 9, 2013)

Daniel Michael said:


> I have a water pipe underground that enters through the basement wall that leaks around the pipe when it rains. The leak stops sometimes once the ground is saturated. Foam sealant was originally used. I have dug down to the pipe and am seeking the best diy method to fix. After much web searching I may do foam again around the pipe, fill in dimple with hydraulic cement, then roofing cement, 6 mil plastic, roofing cement again, and another 6 mil plastic. Now, I wonder if I should fill hole with the clay soil, sand, or gravel to facilitate drainage?


A couple months ago Mom's water line broke underground. We had a guy come in and dig a new trench and put the new line in. He knocked a pretty big hole in the basement wall so after everything was done he took a bag of hydraulic cement and just through it into the trench at the hole in the wall and backfilled.No leaks yet.


Wade


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