Cast Iron to PVC Drain

abright52

abright52

Electrical Engineer
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I recently bought a home that was built in the late 1930's. There are 3 drains going into the basement floor. I believe the main is 4" that connects to the city sewer. There is a 2.5" cast iron that runs into the basement floor and goes over to the 4" Main and there is a floor drain between the two.

I had a clog between the 2.5" and the floor drain. I ended up having to remove the 2.5" CI that went into the concrete to clear the clog. This pipe had a flanged end with what looked like some type of packing and lead filler to seal it up. After removing the lead and packing it pulled right up.

Now that it is removed, I would like to replace it with PVC. The hole in the floor measures 3" in diameter. What do I need to adapt the PVC to this hole and seal it up?

I currently have 1.5" coming down from the Kitchen Sink and Dishwasher into that drain. I will also be adding a wye for a sink in the basement and a wye for a washing machine drain. Any advice on sizing the remaining pipe would be appreciated.
 
The sink was already connected via the Cast Iron piece that I am replacing. They were previously draining the washer into the sink.
 
Are your replies helping? I am trying to note what is currently there, if you are not willing to tell me what needs to be done here, why are you replying? The vent situation will be attended to after the drain situation.

Cliff Notes version of my question:

The hole in the floor measures 3" in diameter. What do I need to adapt the PVC to this hole and seal it up?
 
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Plumbing Code version:
All fixtures require a vent to protect the trap seal. The fact that there is a kitchen sink draining down the pipe from above makes it so that line cannot be used as a vent. Wet venting between floors is not allowed by any code that I am aware of. The 3" pipe is an adequate size for the use you are planning but a vent is needed.
 
Why don't you post a pic of what you have there.

Also this 2.5" Pipe is this an O.D. or, I.D. measurement?
 
I am not currently at the house, so I can't take a picture.

The old cast iron pipe has been removed (Still have the pipe, but not with me), but I am going to say that it was actually a 2" ID where it went into the floor. It was surrounded with some kind of packing and lead to seal it. The hole in the floor is 3" in diameter and it tapers in 2-3" down. Not sure of the actual size of the pipe that is in the concrete.
 
As I said, I am not sure what the actual pipe size is......I am not about it jackhammer the floor to find out or to replace that pipe.

I don't recall ever saying that I wasn't interested in doing it right. A little testy, aren't we?

Thanks for the link.
 
Cliff Notes usually imply that you are unwilling to devote the time to properly learn the material covered by the test and are trying to bluff your way through it.

I'm not testy, just not interested in teaching an unwilling student!
 
LOL. Cliff Notes imply that I can only handle one issue at a time. I need this pipe fixed so that I can operate the kitchen sink again. Vent lines for the basement sink and the washer can wait, the drain cannot. It is a matter of priorities, not a matter of right or wrong.
Thanks, anyway.
 
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Cut your 2" cast iron pipe as low as you can after any hub and adapt directly to the cast iron with a no-hub coupling that will transition from cast iron to pvc. Make sure to install a clean out at the base of this pipe (to clear future blockages) and install your new Y above or below the new clean out.

That will get your kitchen sink going until you decide to complete the entire project
 
The 3" pipe that tapers down in the concrete is flush with the ground, therefore I cannot use a coupling. As I said before, the old 2" pipe had a flange on the end and was inserted into the 3" in-ground pipe. Then some type of packing and lead was filled around it to seal it.
 
The 3" pipe that tapers sounds like the hub for the 2" pipe ..from what you are describing. The only sure way to make a decent connection is, to break a little bit of the concrete around this hub and expose the vertical or horizontal pipe to cut it. Either way, you will at the very least need to install a clean out.

You other option, (i'm not sure if they are even available), to find a reducing fernco coupling that will fit the hub and adapt to the 2" pipe.(some states do not approve the use of fernco couplings above ground). Again you will still need to install a clean out, regardless of the outcome (its in your best interest)

If I'm wrong about the hub, I'm interested in seeing a pic of this 3" pipe, but it sounds like a 2" hub.
 
The hub is imbedded in the concrete so his only option at this point is either pouring a new lead joint or, more realistically using a donut.

It would have been nice if he left a 2 " stub so a no-hub could have been used but its too late for that.
 
I remember a few years ago, they used to have a product out that replaced the lead and oakum hub joints . You were able to chaulk the joint with this rope (PC4). It was made from asbestos cement.

You would dampen it with water (not soaked) and pack it into the hub joint with regular chaulking iron . I think they outlawed in in my area because of the asbestos fibres. I haven't seen this stuff in years.

You would be able to transition to pvc with no problem. The more this rope got wet, the tighter the seal would get.
 
I am an Electrical Engineer by trade, so I am not overly familiar with all of the plumbing terms, but I had been taught the basics by my grandfather that has built several homes.

There is already a clean out sticking out a couple inches from the hole. The clog was between the 3" hole and the clean out.

It sounds like the Fernco Donut linked above would do the trick.

It would have been impossible to cut it 2" from the floor due to the configuration of the old pipes, plus it was already pretty loose in the existing "hub". We just removed what was left of the lead and pulled it out.

I am going to go to ******* after work tomorrow to see if I can get the necessary parts.
 
Its gonna be a blast pushing that pipe into the donut... Pardon the expression but when you finally get it in you'll probably agree its like $#@&*%$ a gopher!:eek:
 
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