How to apply caulk to seal water pipe through basement wall

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GoshenPlumber

Goshen Plumber
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My 1 inch plastic water pipe from the utility comes through the basement wall inside a 10 foot long plastic sleeve which runs underneath the front porch. The sleeve runs downhill from the front of the porch to where it enters the basement wall. In the basement, the installers caulked the space between the inside of the sleeve and the outside of the plastic water pipe to prevent any water in the plastic sleeve from leaking into the basement. I do not know what type of caulk was used. The caulk seal lasted for 10 years without any problem.

Recently I had plumbing work done in the basement and I had to re-caulk the space between sleeve and plastic water pipe. Apparently my caulking job was not good enough because after 6 weeks, the seal started to leak - water in the sleeve was dripping into the basement. I used GE Silicone II 100% silicone caulk that I put on in thin layers. See the attached photo.

Questions:
(1) Is GE Silicone II 100% silicone caulk the proper material to seal between the sleeve and plastic water pipe?
(2) Is there some technique I should use when applying the caulk to ensure that the caulk adheres to the plastic water pipe so that the seal does not break over time?

Thank you.

How to seal water pipe through basement wall - #2.jpg
 
The area should be completely dry before applying silicone. Have you checked the water line for possible leaks
 
The area should be completely dry before applying silicone. Have you checked the water line for possible leaks

I did check and I am 100% sure that the water leak is from the PVC pipe and not the water inlet piping.
 
Dig out all of the old caulking, scrape as much of it off the walls of the two pipes as is possible. Of course, be careful not to damage the pressure piping.:)

Then reapply the caulking, starting at the bottom and lifting the water line up off the bottom of the sleeve piping and getting the caulking well back in that opening. Then let the pipe settle back down and caulk the sides and the top, making sure the caulk gets back in between the two pipes.
 
My opinion is this: The initial install was done wrong. I don't want to see you turn this into a huge project where you're tearing up your whole front yard and porch. So, as the others have stated, dry it out as best as you can maybe even use a coat hanger to push cotton balls between the pipes as far as you can to absorb residual moisture until the silicone dries.
Back to my point about the initial installation.
The outside of the pvc plastic sheath is the problem, not necessarily the inside. There should be an 1 1/2" x 1" fernco to seal the outside around the service and sleeve. Even with the silicone on the inside, the space between the pipes will still fill with outside water and eventually leak through again.
You just gotta fill as much of that gap as possible from the inside. When the first install was done, the pipes were still exposed on the inside and outside making the seal with silicone easier and no moisture was involved.
 
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