I want to add a toilet in my basement next to the sewer pip... I had posted this problem a few days ago.. and now I dug up my basement floor to have a look. It seems that the pipe makes a 90 degree bend not too far below floor level. The house is over 80 years old.
In the picture you can see an old joint where a clean out was added some years ago - I put a ruler in there where you can see that the bottom of the clean out was flush with the floor level, and the depth of the pipe to the 90 is about 8 to 9 inches... is this enough room to cut the pipe and leave a stub above the 90 and tie in a wye that will branch out to the new closet flange where I hope to put a toilet? I thought the pipe would go straight down much deeper and give me more room to work. Now I am nervous about trying this -

Thanks for any advice...

Dig deeper and connect to the lateral. Don't forget it must be vented and a motorized drain can not flush by it.

Thanks - do you mean to say that I should dig out the portion of the pipe after the 90, so that I am tying into the part of the pipe that is parallel to the floor, not the vertical portion of the pipe?

And this pipe is vented through the atic roof, does this mean that it is okay to put the toilet here without added additional venting?

Thanks again

Yes, the lateral is the vertical pipe. The new fixture needs an additional vent.

yes, the lateral is the vertical pipe. the new fixture needs an additional vent.

Couldn't he snap in a san-tee just below the hub, aimed either to the left or right of the stack, put in a combo looking up to run the vent, run parallel to the wall to the new closet location, long sweep out horizontally the required distance and then attach his closet bend and flange?

I'm assuming he isn't going to center his new water closet right in front of the cleanout.

Couldn't he snap in a san-tee just below the hub, aimed either to the left or right of the stack, put in a combo looking up to run the vent, run parallel to the wall to the new closet location, long sweep out horizontally the required distance and then attach his closet bend and flange?

Thanks - yes that is what I "thought" I was going to do before I found out how shallow that elbow was located below the cement floor... one plumber thought that because the sewer pipe is vented through the roof in a 4 inch opening, that I could add the closet flange and toilet without "new" venting for the new toilet. What do you think? Are you suggesting that I add a new, smaller vent off the new combo and vent it out of the house lower than the roof, or do I need to put a new vent all the way up through the 3rd floor?

And yes, I was going to put the toilet about two feet over from the spot where you can see the clean out.

I appreciate the help, any more thoughts on the venting? Can I go in that tight space with a chain cutter and cut a couple of inches above the elbow and tie in a wye to the close flange - or is there too little space?

I have an appointment with a plumber, and may just leave it to him...

Thanks - yes that is what I "thought" I was going to do before I found out how shallow that elbow was located below the cement floor...

So, the hub we see in the photo at the tongue of your tape is the hub of a 90?

If so, then my earlier suggestion will not work.


one plumber thought that because the sewer pipe is vented through the roof in a 4 inch opening, that I could add the closet flange and toilet without "new" venting for the new toilet. What do you think?

I think it's a horrible idea -- Doug was right, you definitely need to vent the new closet.


Are you suggesting that I add a new, smaller vent off the new combo and vent it out of the house lower than the roof, or do I need to put a new vent all the way up through the 3rd floor?

I was suggesting a 2" vent all the way through to the roof, or tying it in to a closer 2" or 3" vent that is already going through the roof.


I appreciate the help, any more thoughts on the venting? Can I go in that tight space with a chain cutter and cut a couple of inches above the elbow and tie in a wye to the close flange - or is there too little space?


I know I could, but I wouldn't recommend you try doing it -- Too many variables are involved like crushing the fitting or having the stack come crashing down on you.

I got to be able to sleep at night, y'know.

And as I said earlier in this post, if the hub we see in the photo is the hub of the 90 you speak of, then my earlier suggestion will not work.


I have an appointment with a plumber, and may just leave it to him...

By all means, pick his brain, but don't let him talk you into wet venting the closet into the stack.