I'm in PA and my sewer line has decoupled from the 4" iron sanitary tee(?) going through my basement wall and it has sunken. Please see photos below:


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I was surprised to find that the outer diameter of the iron sanitary tee coming through the wall was only 4-3/8" and the inner diameter is 3-7/8" ...I thought there would be a wide mouth (hub?) at the end for the next pipe to slide into. But the sewer lateral pipe looks like the same diameter! Here's a direct over-head photo of the two:



The sewer lateral pipe may look smaller but I think it might be an optical illusion since it sits much lower ...but I could be wrong too.

I'm willing to dig and dig (about an 8 foot long trench) to raise the pipe up to meet the height of the sanitary tee but I have a few questions:

(1) Once raised, how would I join the pipes together. A Fernco wouldn't fit in the tiny space between the two pipes would it?

(2) How did they used to be joined together? I see no evidence of breakage or pieces of iron - the place was built in 1979.

(3) Why did the builders in 1979 use PVC for all drains except for the iron sanitary tee going through the wall? It's not critical; I'm just curious. If I have to replace it, I'd like to use PVC and am wondering if it's not allowed or something.

Thank you for any input!

 

I would dig a trench out about 6' long. Then cut your existing cast iron drain line and convert to PVC including replacing the sanitary T with PVC.

As for why your house was built that way it's hard to say. Maybe different plumbers/contractors did the drain line and house piping. I have seen quite a few "liberties" taken with drain lines. I have seem some like yours where the ends of pipes were just aligned but not joined. I'm surprised yours has worked this long without tree root or clogging problems.

 

Thanks a lot for the advice!

I hate to remove the iron sanitary T because I'd have to mess with the beautiful seal through the foundation wall.

But if I do a replacement of the pipe, I still don't know how I'd squeak the rubber joiners on; these pipes are immovable!

I don't know how long that cast iron pipe will go; I fully expected PVC because the plentiful clean-outs on the property sticking out of the ground are PVC. Here is a photo with a clean-out only about 6' away from the sanitary T/block wall:



We've been having clogs and that's how I discovered the offset. We are even getting water in the basement when taking a shower. We just bought the house. Luckily, there is a 2nd sewer line exiting the house where we can run water/toilets/showers.

It's below freezing here and I have a little while before I start some serious digging - as soon as the temps hit the 40's, so I am just trying to figure out what to do.

 

I don't know what the standard length of 4" Cast Iron Pipe was/is; but I think I''d opt to just did up that first length and see how it's fitted to the next segment (and what the next segment is comprised of.

Then you can decide whether to re-install that length or replace it, and 1 or 2 Fernco Couplings won't be a problem to install.

Your situation reminds me of my 1832 house where I followed PVC inside to Cast Iron going through a Field Stone Wall then entering Clay with Oakum joints; followed by some Orangeburg Asphault/Paper Pipe, and finally back to utilizing PVC which terminates at the Septic Tank.

The responsible parties are now deceased; I own the System !

 

That green pipe at that clean out looks like SDR 35.. A different size then PVC... Cast iron is also different size then PVC and a mission coupling no hub will need to be used...

IMO dig it all up to the clean out and show us that..

I would replave from house to clean out... You can leave that Y if its good shape...

 

You can install a banded no-hub coupler without moving the pipe, they are perfect for the job.

Cut the ends of the cast iron clean and square.
Slide a no-hub on each end. Loosen the metal jacket and slide it back.
You can then fold the rubber sleeve back over the ends of the cast iron and insert your new piece of ABS or PVC.
Cut your new piece just a tad shorter, fold the rubber back again over your new piece.
Slide the metal jacket over the rubber and tighten the screws to 60 inch pounds.

 

Great replies - thank you everyone!

Lawrosa: Here is a zoomed photo of it: I guess it does look like SDR (I'm still learning what that is)



Handyone: Yes! That's the info I needed. I don't know if I would have thought of that, because my mind was locked into joining the existing pictured pipes together, not replacing a new cut out segment which would work. I also suppose if I can raise the existing pipe up high enough, I can get one of those rubber couplers on (folded back onto itself), then lower it to join the pictured pipes (no additions or subtractions).

Question (1): I see some call them Fernco couplers, or mission couplers. Is there a difference? besides making sure they are underground rated, do I need to know anything else special to get the right one?

Question (2): If I cut the iron pipe to put in a new piece of PVC, what do I cut it with? I have a reciprocating saw but will a long metal cutting blade work OK with such a beast?

I ask all of this because I have a window of only two days to repair this on Tuesday because it will finally be above freezing and it will have stopped raining. I need to know as much as possible so I can repair it in two days to fill everything back in before the rain and then freezing temps begin right after (according to the weather report).

 

1. Mission and Fernco are brands. Both companies make numerous different types of couplings so saying whats the difference depends on what couplings your talking about.

2. You can use a reciprocating saw. Buy a pack or two of high quality metal cutting blades. Cast iron will dull the blades so you may need several to get through the pipe. If your trench is narrow you'll be working in an awkward position so you may tire and end up bending a blade so it's always a good idea to have twice as many blades as you think you'll need.

Yes, doing the work can be done in two days. The only thing we don't know is how deep your pipe is buried. Digging the trench will be the biggest variable. I do repairs like that and it usually takes about half a day but I cheat and use an excavator for the digging. Having all your materials and tools ready and on site will make things go much faster.

Buy or find a short 12" nibblet of 6" pipe to use as a conduit through the wall. Under most current codes you'll have to install a conduit through the wall then run your drain pipe through the center of it. A rotary hammer with some masonry drill bits and a chisel bit will make removing your old fitting and enlarging the hole much easier. The conduit can be mortared into your wall with ordinary masonry mortar or hydraulic cement.

 

Today I started digging to give myself a head start for tomorrow's big dig and saw some crushed stone/gravel which I assume is surrounding the sewer pipe.

What exactly is the function of gravel? Is it to stop roots from finding water?

I have searched the internet for the answer but everything I read says to just do it ...never explaining WHY.

Thank you.

P.S. I will be posting photos tomorrow of my findings. So far I see cast iron pipe and some cavities under it. I am wondering if these cavities were made from leaking water washing dirt away or from settling - I don't know what's the most probable due to lack of experience.

 

As I said dig it out so we can see where the transition is to the clean out..

After repair the pipe should rest in sand and get a top covering of sand as initial fill before final fill dirt..

 

So what is the function of the gravel/sand? What does it do?

 

Prevents large rocks from damaging the pipe during fill.. Also give a firm base so when backfilling pipe dont break or get bellys... sags...

Waste pipe needs to keep constant pitch...

 

Dirt is very difficult to compact properly so it won't settle. Clean, crushed #57 stone is naturally 80%+ compacted just by pouring it out so it makes a good base for underneath a pipe.

 

law and Pilot: Thanks for the quick reply! OK, that makes sense since the SDR that's used is very thin and flexible. I don't trust SDR myself, but it's what they used at my place. And it was used underground with the downspout/gutter system and it's getting smashed from the weight of the ground because of how thin it is.

Anyway, I got a lot dug out and here's what I uncovered:



The white pipe you see is where the downspout empties into; I had to cut it off to get work done. BTW, the fittings were not glued and there are roots everywhere (I'm guessing not glued on purpose?).

I was looking forward to replacing the cast iron with PVC UNTIL I uncovered a cast iron wye (pictured) which connects the other sewer line we have nearby. Nooooo! I was exhausted and completely demoralized when I found the wye. I didn't have the energy to start digging another vein.

I found the following:
* The two fittings after the wye looked like 45 degree fittings
* All cast iron fittings were connected with a rubber gasket, not lead
* The last 45 degree fitting was causing the last length of pipe to be angled down too far and was pushing down with great force ...maybe causing the problem. This probably should have been a 22-1/2 degree fitting.
* The top length of pipe which joints the 1st fitting is really crooked (see photo) but no leaks
* There was NO trace of a connector joining the last length of pipe to the house (combo wye)!! How is that possible?

As I said, I didn't have the energy to start digging out a perfectly good cast iron vein, so I tried cutting the last 45 degree fitting hoping the non-hub part of the fitting was the same size as cast iron pipe - and it was, meaning a rubber coupler would be a good fit.



I used a 22-1/2 degree PVC fitting and the angle of the pipe seemed perfect.



...and I completed the crushed stone with a pounding/compression.

 

I am still in shock not finding a connector or evidence of a broken connector where the cast iron pipe meets the combo wye going through the block wall.

Another note for those reading this in the future for help: When cutting cast iron, I found out there is a special blade made for iron that fits a reciprocating saw. Instead of teeth, it had what looked like sand glued to the edge. It was labeled "carbide grit" and it took about 25 minutes to get through a 4" pipe!

Here's a close up of the cast iron wye I came across:

 

I'm glad you finished this job successfully, and documented your activities.

I find myself frequently re-living some projects and reading what I wrote to be enlightening because while I won't make notes for myself, I will take photos and write in more detail in order to post on forums like this . . . . even if it's doubtful anyone else will read it. The fact is that I do, weeks months and years later.

That may not make sense to someone who hasn't been there.

 

Very nice job! It's always nice to see a well-completed project.

 

Yup good job... Thats the right way to do it...

I would of replaced all if it were my home..( second y etc up to the sdr.)

Also that fernco worked good on the right but technically it needs to be a banded no hub coupling..

Code as I know it anyway. But for what you were up against Its a great repair..

 

Thanks to everyone for all the advice and for the encouraging comments at the end. I am happy to post conclusions and photos for those in the future that find these threads who need help. I know I benefit greatly from all the past threads whenever I need help too!