Can a Toilet pipe sink and rise again?

justanotherdriftwood · Feb 3, 2009

I need to move my toilet to the other side of my basement bathroom. Using a jackhammer, I ripped out the concrete only to discover a large 4" pipe running parallel to my existing toilet pipe, but it is exactly in the way. My new toilet has to be on the other side of that pipe (which is apparently an old asbestos pipe connected to my upstairs toilet).

I'm sure it's not recommended, but is it possible to loop my existing toilet pipe over or under the other pipe in order to get around it? It would essentially be an additional P trap placed over top (or under) the other pipe. Will the toilet still drain?

Gary Swart · Feb 3, 2009

Can't do it. No double traps. It sounds like you have a serious problem. It might be worth the expense to have a professional plumber deal with this one. You sure don't want to end up with a toilet that won't work right, and I think this is more than a band-aid repair job. There are times when all of us DIY have to admit we are in deeper that our knowledge base, and this may well be one of those times.

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Krow · Feb 3, 2009

justanotherdriftwood said:
(which is apparently an old asbestos pipe connected to my upstairs toilet).

Why not abandone the old toilet pipe and cap it off, then cut in a new Y in the 4" pipe that is , apperently, in your way. Just make sure you vent your toilet to meet your local codes.

hj · Feb 4, 2009

drop

Running the new line under the obstruction would ensure that the toilet would NEVER flush properly, if at all, regardless of whether a double trap were allowed or not.

justanotherdriftwood · Feb 4, 2009

Thanks for the quick feedback. I assumed as much, but wanted to make sure. I'm going to redesign my layout to make the toilet work on this side of the obstruction.

Krow, you're right, I probably could tap into the other pipe, but I would prefer to leave well enough alone. That pipe is responsible for all my drainage going out to the sewer, and I don't want to risk making a critical error and mess everything up. I want to work with pipes that are already connected to that line.

Thanks to all for the quick feedback.

Howard M Emerson · Feb 4, 2009

justanotherdriftwood said:
I need to move my toilet to the other side of my basement bathroom. Using a jackhammer, I ripped out the concrete only to discover a large 4" pipe running parallel to my existing toilet pipe, but it is exactly in the way. My new toilet has to be on the other side of that pipe (which is apparently an old asbestos pipe connected to my upstairs toilet).

I'm sure it's not recommended, but is it possible to loop my existing toilet pipe over or under the other pipe in order to get around it? It would essentially be an additional P trap placed over top (or under) the other pipe. Will the toilet still drain?

Is it possible to raise a platform under which you can run the new drain pipe into the old one? You may be able to get away with only having to raise it a few inches if you dig down into the slab and then add a short 'rise' onto the floor area needed for the toilet.

I've seen it done as a nice functional design detail.

HE

Gary Swart · Feb 4, 2009

Placing bathroom fixtures on platforms is the sign of a true hack. It will haunt you for life. Spend the time and money now and do it right. If you don't have the confidence to DIY, then hire a plumber. You are already investing a great deal of time and money in this project, don't end up with a makeshift job with questionable plumbing that you will forever be making excuses or apologies for. The added expense now will soon be forgotten, and you'll have a bathroom you can show off and be proud of.

Krow · Feb 4, 2009

justanotherdriftwood said:
Krow, you're right, I probably could tap into the other pipe, but I would prefer to leave well enough alone. That pipe is responsible for all my drainage going out to the sewer, and I don't want to risk making a critical error and mess everything up. I want to work with pipes that are already connected to that line..

If you dig a little further down along the 2 pipes, you may end up finding where the existing toilet pipe ties into the 4" main line. I'm going to guess 2-3 Ft downstream of the existing flange.

hj · Feb 5, 2009

floor

Interesting that you can use the terms "raise the floor" and "nice functional design" in the same letter and make it seem logical. I would consider them so mutually exclusive that it would be impossible to do so.

Howard M Emerson · Feb 5, 2009

hj said:
Interesting that you can use the terms "raise the floor" and "nice functional design" in the same letter and make it seem logical. I would consider them so mutually exclusive that it would be impossible to do so.

HJ,
Just because you can't picture doesn't mean it can't exist, and I've seen it done many times, very well. By 'very well' I'm saying that it did not scream 'Oh, geez, I guess you screwed up'.

Not all bathroom areas lend themselves to doing it, mostly because the area is too small. Some times it's just best to accept that you can not redo the bathroom in a major way because of certain structural elements, such as drilling 4" holes through consecutive joists, etc.

I suppose that when he drills enough holes in the post-tensioned slab to undermine the structural integrity that he can always say he didn't want to look like a hack.

HE

Can a Toilet pipe sink and rise again?

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