I have a basement toilet. Currently, the drain is a 3" copper going into a cast iron fixture thru the slab. I think they jackhammered up the floor and attached into what used to be a floor drain, or some sort of similar drain - the hole isn't very big so I don't think they installed a T in the main drain at the time -it was already there. The joint is aparently lead(haven't checked).

As you enter the room, there's a sink then a toilet to the left, and a (tacky tiny sheet metal) shower to the right far corner. Everything is setting on a plywood/linoleum floor on 6" subjoists, so most of the piping runs above the slab floor level.

I want to move things so the sink(closest), toilet and right-hand taps bathtub (farthest) are on the right as you walk in. This would put all three backing against the same interior wall. I would also like to lower all the piping and maybe pour some form of concrete over the whole instead of a wood floor, and use ceramic tile to finish it all nicely.

Can I pour concrete over it all?

The toilet drain (others are tied to) currently runs into a Tee where the vertical part is a clean-out under a trap-door in the centre of the room. I envision a horizontal (sloped) 3" run with a slight corner (1/16? Is there such?) so the clean-out is accessible from the furnace room behind the toilet. Is this OK?

How high above the horizontal must a toilet be? Whatever will fit?

How does it vent - must I tee off befor the toilet, or just vent tee by the clean-out? Was there a requirement for venting before the fixture?

Bathtub - other than (obviously) the drain horizontal must be below the bottom of the bathtub, what are the requirements? How would it hook into the 3" toilet line - between the toilet and the cleanout, or between toilet and drain? (Latter sounds like a mess of T's and parallel pipe by the 3" run...)

If I can run a long curve(is that the right word? Not sharp 90 deg) to drain from horizontal 3", a curved sweep on a T vertical to the toilet, a slight bend up (if such exist) on the horizontal then a pair of T's for the tub and sink drain after one for the vent before the cleanout. Or can I have a long sweep or 45 up to a clean out at the end of a sloped horizontal 3" drain? Or should I have a 45-T to the vent from the toilet run?

I gather the other items draining can cause this to be a "wet vent" if I don't put a vent T between the toilet and the drain.

Fortunately the vent for all this is right there, so I assume I just run the vent for each fixture vertical, tie them together at the ceiling with appropriate sloped horizontal that connects to the exting vent, which goes straight up to the roof... )

Hope this is clear. Any comments? Help! THANKS!

One question. Will a permit be pulled and will this remodel be inspected?
Or will you be doing this job yourself? Regards, Tom

Probably do the job myself. I had a rough quote of $2000 from a local plumber a year or two ago, if I did all the concrete breaking. A plumber I met said he didn't feel comfortable doing the job without the backing of a plumbing firm in case an inspector raised heck. I'm assuming this means it's "not quite code but acceptable work-around" territory.

However, I'm just relocating existing fixtures in the same room, so technically I should not need a permit and inspection.

In the end though, if it doesn't work well, if it causes problems, I haven't gained anything by putting in the plumbing badly. I want a setup where everything drains, nothing gurgles, and nobody has cause to complain when I sell the house.

The current bathroom has painted plywood walls, a trapdoor in the linoleum in the middle of the floor, ancient pink fixtures and a tiny tin shower stall and less than 6 feet headroom where the heat duct goes overhead. Everything is poorly located. Just replacing fixtures and applying pretty stuff would be a waste of effort.

When done, there should be a 5-foot sloped 3-inch drain and all the rest would be against the wall visible and accessible from the furnace room side; a wall about 7 feet by 7 feet, vent at top.

No, if the fixtures are being moved, then so is the plumbing to the fixtures, so you do in fact need a permit for this job.

Growler's correct,
You're changing the configuration of the existing drainage system and that calls for a permit. If you wish to stay in code you're going to hafta to increase the main to 4" under the pour. We are allowed a three inch main on the second floor but must keep the main and toilet at 4" under a cement pour.
In my area a home owner's allowed to pull a permit and do his own work.
Check with your building department. If you wish you can post afloor plan
And one of us can lay out the drainage for you. Regards, Tom

Too many people misunderstand the reasoning behind pulling permits and having the work inspected.

Having the work inspected to make sure it meets current plumbing code and that it will function properly is a way of making sure everybody's butt is covered -- As well as to ensure that unsanitary conditions are not allowed occur.

I just flat-out will not do un-permitted work for anybody, and if the homeowner insists, then I pass on doing the job.

I understand your position.

What I'm trying to understand is:
- whether I can move the clean-out from the middle of the bathroom to the wall behind the toilet(in its new position); I saw a comment somewhere that the cleanout could not be the horizontal continuation of the toilet drain. Can I put a 45 on the end?

-the sink and toilet (and previously a basement kitchen sink) all drained into that existing toilet drain, with proper venting, it seems. I just want to understand what I have to do to replicate that. (The shower is it seems downstream from the toilet but properly vented... )

-I'm curious if I can actually lower the entire plumbing setup a few inches. How tight can a 90deg horizontal for a toilet be? Did the cleanout need to be on that tee?

See, to do this - I have to tear out the walls, floors and fixtures to see where the pipes are now. (All I can see is the pipe going to the toilet in the trap door). Then I have to chop up several square feet of concrete slab. Then (worst? Case) shell out $2000 for plumbing.

Better to know this is OK, normal, and not something where the plumber or inspector will say in the middle - "sorry, no dice! There's no way to make it work."

Scouring the internet gives tantalizing clues but no firm answers, which is why I ask this site.

As I said - I want it to be correct and functional.

[QUOTE=md2000]I understand your position.

You can move it to the wall behind the toilet as a continuation of the toilet vent, but the vent to that point will have to be 3", you can then bush down the top of the clean out tee with a 3"x2" bushing and continue the vent up as a 2" vent.

How far down you can go is dictated by how low the pipe you are connecting to is, everything upstream of that connection point must be graded a 1/4 of an inch per foot.

As for how tight a 90 you can use:

Horizontal to horizontal must be done with a long sweep 90.

Horizontal to vertical can be done with a medium sweep 90.

Vertical to horizontal must be done with a long sweep 90.

Excepting the toilet 90 where it connects to the closet flange, this 90 going from vertical to horizontal can be a medium sweep.

A clean-out can be installed on the vertical portion of the vent, but in your case the clean out must be at least 3"


If the $2000.00 price tag is for the entire plumbing job, from groundwork, top-out and the setting of the fixtures, then you are getting a real bargain.

The plumber should be able to tell you if you have the depth to do what you want to do simply by seeing just how deep the pipe this all ties into is buried.

The cast iron bell (is that what it's called?) is about 3 inches below the slab, so what you're saying is that the lowest I can go is the height of a medium sweep elbow into that.


So I can continue the toilet drain behind the toilet on a sloped horizontal, then with a wide sweep, come up behind the wall behind the tank and install a 45 Tee for a clean-out; then reduce it to the vent pipe size. That extra foot of horizontal behind the toilet is OK and the clean-out location is OK.

Can I attach the sink and tub drain (1-1/2") to the 3" drain between the toilet and the long sweep to vertical? Technically this would make the toilet a wet vent for about a foot, if I understand the terminology. (Sink and tub would have their own vertical vents joining the toilet vent along the ceiling.)

Right now those drains join the toilet drain along the horizontal between the toilet and the elbow to the sewer and I haven't torn up anything to see what the toilet does for venting. Maybe it relies on the sink vent?

Anyway, thank you very much for your answers, they are quite informative. I'm in Canada but I assume the plumbing codes, barring local quirks, are pretty similar. I just wouldn't want to go to the inspector with a plan and have him say "you have what already installed??? You have to rip it out right now..."



No, that was me doing ALL the demolition and concrete work, and they just do the piping. (and put their name behind it). Mind you, it included the water supply too, which is also right there already and just needs some last-7-foot feeding. Not outrageous, but not cheap either.

I'm assuming I can somehow raise the floor - probably using concrete or something, rather than wood joists. I guess burning piping in concrete is a whole other topic to talk about. I just would like to raise it substantally less that the 6-plus inches it is now raised. Oh, and replace the heating duct from 9-inch deep to something less ( 4 inches?), since this is the dead end that only feeds 2 registers above. No end of questions when you start to renovate. I'll figure out how I'm running the pipes before I worry about floor cementing or ducting.

3" from the top of the tie-in pipe to the top of the finished floor isn't going to give you enough room to do what you want to do.

From what you've told me, keeping the raised floor level is your only option.

Have you considered just making some cosmetic changes to the existing layout?

Replacing the toilet with a 1 piece Toto, putting in a Neo-Angle shower at the old showers location and putting in a double vanity with two sinks would greatly enhance the look of the bathroom.

And pour the floor if you like and finish it off with octagonal tile on the floor and wainscotting on the walls.

In other words, it might be more practical and more cost effective to dress up what you already have.

And you can probably still cut a new fitting in at the clean-out in the floor and run the clean-out to the mechanical room you mentioned earlier.

Just some thoughts.