Repair of partially collapsed sewer main drain

[Nwoodard34]

Hey all, this is not a DIY project (for me anyway) but I did want to throw it out there to you guys that are way smarter than me about this kind of stuff so I can make sure I manage the project correctly.

House is built in 1963 and has what looks to be cast iron pipe.

We bought the house in November and started having backup problems in the basement bathroom and outside drain (which is connected to sanitary sewer) in February. After a couple of snakings that only solved the problem for a couple of days at a time, we had it hydrojetted and the guy ran the camera through:

As you can see at the 35 feet mark in the first video, the drain is partially collapsed. Signal locator showed it is right under the foundation wall. Got a quote to fix it from the inside (busting up concrete in the basement) that was for either $2,500 or $3,500 (the guy had a very thick accent) but regardless it wasn't in the budget at the time to fix, so we rolled the dice to see if a good cleaning after 50+ years of grease and hair would solve the problem. 2 months later, last week, we had the same problem so it is time to address it.

My questions are:

1. Are my options to repair it from inside or outside? Outside repair would require about 4.5 - 5 feet of digging since the basement is below grade, but it is my preferred option since that half of my basement is a converted studio and is rented right now so I would prefer not to disturb his life (and my reviews/rental business).

I also don't have any hardscaping or landscaping that would be disturbed from an outside dig except for a mulch bed and some dead bushes/flowers that need to get removed anyway.

2. Any huge benefit of one over the other as far as the repair itself goes?

3. Should I go ahead and have the pipe replaced from the foundation out to the city tie-in while I am at it due to age, or can this be explained from the house settling on top of it?

4. Is a sewer main warranty an option here? They have a 30 day seasoning period and I should be good for that since I was for the past 60 days between jettings but would need to look into their view on pre-existing conditions and if the foundation wall is considered "inside" (which isn't covered) our "outside" (which is).

Really appreciate your thoughts and advice.

 

[hj]

well, two things. The guy who did the upper video must have been double parked as fast as he was moving the camera, and second one was fixated on that one position because he NEVER moved the camera. You need someone between the two who gives you a better picture, but cast iron pipe does NOT "collapse", it cracks and breaks and I do not see that in either video.

 

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[Reach4]

Alternatively, you could see if you could find a local drain cleaning specialist that uses a conventional mechanical cutter could clean things out. Warn him that somebody thought something was collapsed but that that was a suspect diagnosis.

 

[Nwoodard34]

well, two things. The guy who did the upper video must have been double parked as fast as he was moving the camera, and second one was fixated on that one position because he NEVER moved the camera. You need someone between the two who gives you a better picture, but cast iron pipe does NOT "collapse", it cracks and breaks and I do not see that in either video.

The second video I asked him to get a good shot of the spot where the issue is. If you freeze the first video at 1:18, that spot is what is in focus in the second video. He was the hydro jet guy, so he was probably just running it through to make sure there wasn't any crud left on the pipes.

If not a collapse, can you tell at all what is narrowing the 4" pipe down to 2" or so at that exact point?

 

[Nwoodard34]

Alternatively, you could see if you could find a local drain cleaning specialist that uses a conventional mechanical cutter could clean things out. Warn him that somebody thought something was collapsed but that that was a suspect diagnosis.

So you're thinking that the narrowing might be due to crud still left on there than an actual mechanical issue with the pipe? that sounds plausible--when I remodeled the bathroom a few weeks ago I had to take a dremel tool to open up the sink drain pipe (cast iron) due to all the hardened crap that was on there.



Though plausible, it would be an awful big coincidence I think that that buildup would happen right at the foundation wall absent of any other mechanical issue, no?

 

[Nwoodard34]

Any other advice out there about what to do next? The pipe is definitely getting clogged somewhere and that mark at 1:18 is the most logical choice. Can anyone tell from the video if it is just a 45 bend (was suggested on another forum) and not a partially collapsed area? Do I just need to get a plumber out to do a better camera job to tell for sure?

 

[Nwoodard34]

well, two things. The guy who did the upper video must have been double parked as fast as he was moving the camera, and second one was fixated on that one position because he NEVER moved the camera. You need someone between the two who gives you a better picture, but cast iron pipe does NOT "collapse", it cracks and breaks and I do not see that in either video.

HJ: do you have any idea from the videos what would be causing the clogs other than a collapse? Does my theory that the narrowing is due to hardened crud like I saw on my bathroom sink have any merit? You seem knowledgeable so I'm hoping you can offer your expertise here. Thanks

 

[WorthFlorida]

Hello nwoodard34,

Old homes have old bones and arteries and you have a perfect example of what wrong with iron and galvanized drain pipes. There are millions of homes out there with cast iron drains and they always seems to eventually fail. If you can afford the budget I would change it from the foundation all the way to the street connection with PVC. PVC never gets coated with crud. You might get a block because something too large got put down the drain (toilet) but that is rare (happened to my neighbor). Once it is installed your worries will be over. As you upgrade and remodel it be very easy to replace the steel pipe with PVC and make the connections. It's a big bullet to bite and a home improvement loan may be the only way.