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My house is 15 years old, and ground water has suddenly started to leak into the basement around a pipe that passes through the poured concrete foundation. The method of installation complicates the repair.

Situation

An iron pipe sleeve (roughly 4"D), is sealed to the wall with spray foam. A 3" PVC drain pipe passes through the sleeve, with more foam sealing between it and the sleeve.

Leakage

There aren't signs of leakage between the two pipes, it's all between the sleeve and the wall. There appear to be small leaks between the foam and the concrete. However, much of the water enters around the sleeve, between it and the foam.

I cut away most of the foam to find the source. Some pieces cleanly separated from the concrete, indicating that it wasn't bonded. Around the sleeve, all the foam cleanly pulled off. Embedded in the foam was a layer of black. It looks like water rusted its way down the sleeve. The surface of the pipe remained bonded to the foam, and water leaked under that. There is some powdery residue on the pipe that's a mixture of black and some rust color. The sleeve otherwise seems virtually intact.

Issues

  1. I can try to remove the rust in the exposed area, but the sleeve will rust again, making it hard to do a permanent repair.
  2. The foam didn't make a permanent seal with some of the concrete, making me wonder whether it's suitable for this application.
  3. Trying to seal with hydraulic cement will require grinding away all traces of foam for it to bond well with the concrete wall. The area doesn't have great work access, so this would be difficult, messy, and involve risk of damaging surrounding plumbing. Also, can you even use cement on iron (thinking rebar issues)?
  4. My understanding is that the purpose of the sleeve is to facilitate servicing the pipe if needed. An approach like encapsulating the opening with epoxy would require bonding to the PVC pipe to be permanent.
  5. The exterior of the wall is inaccessible; all work must be done on the inside.

Solution?

Is there a good, permanent solution? What I've considered:

  • I could just clean it up and apply new foam. Hopefully it would hold for another 10-15 years (and maybe become someone else's problem).
  • I could clean it up and use hydraulic cement to seal it. That would be a lot more work, and also temporary because of new rust.
  • I could encapsulate the opening in epoxy. If I ever need to service the pipe, just deal with it then.
  • I could try to seal the hole by injecting Gorilla Glue around the sleeve as far as possible into the hole (syringe with long needle). That expands as it hardens, after which foam (or cement?) could be added to further seal it. That might prolong the time until another repair is needed.
  • Wrap the pipe with self-fusing silicone repair tape, and then fill around it with hydraulic cement (no idea whether it would work).
  • I can't think of another material that is waterproof and permanent, cures in the presence of water, stays put while curing under pressure, and bonds with wet surfaces.

Pictures

The location is blocked by a utility sink and a water heater, so it's difficult to get at the pipe, to see what you're doing or work on it, and to take pictures.

enter image description here

There are actually two pipes running through the wall in this location. To the left of the subject pipe is the water line. Some of the concrete around the two pipes was broken away at construction time; that was all filled with foam before I removed it. There's still some remaining above each pipe sleeve. There's also some leakage around the water line sleeve due to gaps in the sealing foam; that one isn't an issue because the sleeve is PVC and sealing that one is straightforward.

enter image description here

This view is the right side of the problem pipe.

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    A picture would be helpful.
    – HoneyDo
    Commented Aug 5, 2020 at 4:15
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    It is possible that your footing drains have started to plug up and that’s why there is enough water there now when there was not before. Do you have a sump pump , is your basement a daylight (walk out) basement. Your ideas could work and seal things temporary but if it is a drainage issue there will be leaks until the problem is fixed.
    – Ed Beal
    Commented Aug 5, 2020 at 13:50
  • @EdBeal, good observation. The basement isn't daylight. There's a sump pump. It doesn't appear to connect to the perimeter drain, but there's a gap around a PVC feed pipe (from floor drain and stairwell drain), and the gravel under the basement floor drains into the sump through that. The property is adjacent to a community water catchment field, and the water table is often high. So there has always been pressure on these openings (the water pressure isn't recent). Sounds like I shouldn't count on any fix being permanent.
    – fixer1234
    Commented Aug 5, 2020 at 17:27
  • Fixer I have seen two many times where someone used hydraulic cement and when that failed called us. Even solid concrete walls will leak when not sealed from the outside. If possible getting your drains connected will keep that area from leaking but raise your power bill for the sump pump, connecting them may be much cheaper than trying to seal and having it leak, would I try a foam plug? Sure closed cell is best but more expensive. Clean up make a cardboard plug to go around the pipe fill the void and let the foam push the cardboard out making sure it fills to the top. I used a plastic bucket
    – Ed Beal
    Commented Aug 5, 2020 at 18:43

1 Answer 1

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I would remove all the foam you can from the outside of the metal sleeve pipe, then coat the pipe with epoxy, then fill the rest of the material with any suitable concrete patching material. You can easily find epoxies that bond to metal and concrete, and bond when wet - many will even cure underwater. So you know it will bond to both the pipe and the patch material.

You could use all epoxy as long as it can be mixed thick enough to work on a vertical surface but if there's a lot of material to fill in, it might get expensive.

If you're concerned about the rust on the metal sleeve pipe, you could treat it with a rust stabilizer product. These products turn rust to a black oxide and work OK, depending on how deep the rust goes. I don't know if you could determine for sure the epoxy will bond to the black oxide although I suspect it would. It may not be that important since the sleeve is not structural and the epoxy will hold things together to some extent.

Gorilla glue or other polyurethane glue is popular (great, great marketing) and performs pretty well for its intended uses but it's one of the most overrated products around. It's not as versatile as people want it to be. It is pretty close to expanding foam, in fact it foams up to fill gaps. I would not try using it for anything here.

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