Planning on moving main stack

acjensen · Aug 29, 2007

Hi all, this is my first post, but I've been a frequent reader on this forum for quite awhile.

My first question is - is there any reason that my main soil stack must be all vertical? It sits inconveniently 3 feet from the outside wall of my basement, and I'd like to finish that room and eventually turn it into a laundry/bathroom I'd like to bust up the slab and move the pipe to the outside wall, making an 90 near the ceiling and going down below the slab and meeting back up with the sewer line.

If that's kosher, I've got a couple other little questions about how to tie things back into said stack...

mainly the toilet, see pictures below.

Your expert help would be greatly appreciated!

acjensen · Aug 29, 2007

i should clarify, i didn't do that hack job with the laundry sink into the cleanout... it was like that when I bought the house, one of many things I hope to correct by doing this. Also, the toilet is a 4" to 3" reducer, wouldn't this be a great place for clogs to happen? It doesn't help that I have an older american standard low-flow toilet...

Eventually want to replace with a TOTO!

Sponsor · 2022-01-29T12:20:58-0800

Cwhyu2 · Aug 29, 2007

The best way that I can see is to open up the the floor and extend the
horizontal pipe under ground to where you want your stack to come up.

acjensen · Aug 29, 2007

got that, the things i'm more concerned about are above the slab... i was wondering if option 1 or 2 is best for the wc meeting the main stack, or if there's a third way that's better?

acjensen · Sep 3, 2007

i'm thinking option 2 is best, with the vent slightly up from horizontal on the toilet line. I'd like a second opinion, though...

Leejosepho · Sep 4, 2007

Option 2 looks fine to me, and yes, I would definitely get rid of that 4-to-3 reduction under the toilet.

hj · Sep 4, 2007

pipe

Option #1 would be completely improper. #2 is better but you might still need a tub vent depending on how the connection were made, and there is almost no "legal" connection with that arrangement that would not need a separate vent. And, I ALWAYS install toilets with that "4 x 3 reduction".

acjensen · Sep 4, 2007

i was planning on venting the tub... thanks for the advice, what is the purpose of the 4x3 reducer? I'll do it that way if there's good reason to. Is it because the 4" pipe can have more air in it?

Patrick88 · Sep 4, 2007

option 2 looks good and pull vent for bath. I think the 4" to 3" is more a personal pref more than anything i 4" to 4" works and 3" to 3" works. If you ask 10 plumbers how to do something you will get 10 different answers. more or less

Leejosepho · Sep 4, 2007

hj said:
I ALWAYS install toilets with that "4 x 3 reduction".

Even horizontally, like in the picture?

Geniescience · Sep 4, 2007

option 3 is with a vent going into the tub line. Can you draw that?

acjensen said:
... making an 90 near the ceiling and going down below the slab and meeting back up with the sewer line. ...

What dimensions will the ninety degree turn take in your basement ceiling?

David

acjensen · Sep 4, 2007

geniescience said:
What dimensions will the ninety degree turn take in your basement ceiling?

i guess i don't understand this... the 90 is from horizontal to vertical, if that's what you mean, not all horizontal. ar3e long sweep 90's preferable at any point in option 2?

acjensen · Sep 6, 2007

overhead drawings

here are a couple overhead drawings of the existing and proposed layout.
the scale is 4 squares to the foot. I think the proposed one looks good, let me know if you guys see anything that needs work.

Statjunk · Sep 7, 2007

I remodeled a basement once where I encountered that same problem. Instead of moving the stack, I moved allthe services over to the stack and created a large utitity room. I remodeled the rest.

Is that a possibility in your case?

Just seems like a lot of work to move a pipe 1.5'.

Tom

Got_Nailed · Sep 7, 2007

I would use sweeping 90* bends.

As far as the 4 to 3 I will always use 4 inch unless I have to run a pipe through a 2x4 wall then I use a 4 to 3.

acjensen · Sep 7, 2007

statjunk said:
Instead of moving the stack, I moved allthe services over to the stack and created a large utitity room. I remodeled the rest.

Is that a possibility in your case?

Just seems like a lot of work to move a pipe 1.5'.

I COULD, but the reason for doing so is that this is my laundry room, and i'm making it into a laundry/utility/bathroom and i'd like the extra space...

the rest of the under slab plumbing is on the other side of the room and is unrelated to the main stack, i just want to move it to buy some room. As for it being extra work - this kind of project is exactly what I like to do in my spare time, so i'm actually excited to bust up the slab and reroute the plumbing.

the rest of the stuff, adding a toilet and a shower will be separate posts after i get the plan for the stack nailed down.

Patrick88 · Sep 7, 2007

if your going to add a bathroom next make sure the vent your adding for the laundry is sized also for the future bath.

acjensen · Sep 7, 2007

the vent is going to be 2 inch, is that big enough? (note: this is a separate vent for the laundry tub and the planned bathroom downstairs, and has nothing to do with moving the stack)

acjensen · Sep 8, 2007

Found this on another site, it seems legit, would this arrangement work for my situation?

Here's what the site said: Where there is only one water closet in a stack vented group, it may connect to the vertical stack or horizontal continuation of the stack and remaining fixtures upstream of the water closet must be connected directly and independently to the stack and the uppermost fixture must be connected to the vertical portion of the stack.

...Or should I stick with what we've been talking about... Note, the site I got this pic off of is for Ontario, Canada. Codes are probably different, but physics works the same way there, right?

GrumpyPlumber · Sep 8, 2007

The bathroom group in the photo is wet vented, which is ok in my state but not all.
The toilets a no go, no vent after two 90's vertically.

Planning on moving main stack

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