Venting Possibilities for basement toilet

[wrencher]

I ain't no plumber. I have no intentions of playing the part. But i sure like to know what my possibilities are before I call one in and they tell me i'm dreaming. (or need to dig the whole basement up).

Since I will be laying tiles in the laundryroom shortly; I have decided to investigate the possibilities of installing a toilet and laundry sink piping beforehand. This laundryroom is in the basement. There is a powder room (toilet & sink) on the first floor directly above. Its 3 inch soil pipe goes down the far wall, pick up the garage emergency drain (also 3 inch) and continues down into slab. under which it pulls a horizontal run, crossinfg exactly 4 feet in front of where my planned toilet would be. Since it is a laundryroomn already.... there is a 2 inch vent pipe (dry) very close to where the planned sink should be. In a spur of the moment decision I rented a jackhammer and opened a hole in slab to inspect and see if such plan was possible. If it is I will pull my permits and try to find a willing plumber. But since I seem to have hit a snag.... I need some advice.


Problem 1: I found the 4inch Pvc horizontal pipe a lot higher than I expected. It was actually 1.5 inches bellow the ~5 inch cement slab.

The new soil pipe would run 4 feet (so 1 inch drop) and since it is 3 inch pipe (I gain 1/2 inch) . Add the rise from new slab & tiles install and I should probably pull it off no?
Big Problem 2: How would I vent such toilet? the soil pipe is to high for a vertical or non horizontal hookup and it runs in front of toilet.

Can I use a wet vent from the laundry sink and drop it behind the toilet if I continue the 3 inch toilet pipe behind the toilet....or is this a No No (as i assume) . This wet vent will now have to run almost horizontal from the laundry sink to toilet (below toilets flood rim). but it's a wet vent so is that ok? the laundry sink vent could then rise to 6-7 ft height and then cross to adjacent wall to branch into existing 2 inch vent no?

I included a drawing.
http://i1303.photobucket.com/albums/...ps081d5cce.jpg
or Should i just forget it and run the drain for laundry tub. Stick in macerating toilet?

thanks for suggestions in advance

PS the recessed cleanout is ~8 in down below the floor of the other room and i assume it is the final exit towards the street.

[Terry]

A laundry sink can't wet vent a toilet, however, a bathroom lav can, if it's run in 2"
You would put a 3x2 wye in and point toward the lav. The vent could then connect to the existing vent.

But then this is Canada, and it may be a bit different then that. Maybe someone from the frozen North will chime in.

Though Seattle is North of Montreal.

[mikeplummer]

Terry has hit it bang on....wet vent the toilet via a 2" lav drain and connect the vent for lav/toilet to the existing vent above flood level rim. peace of cake for any plumber

[wrencher]

Thanks. A little confused though. So are we saying that I should forget a laundry sink and just install a regular sink (lav)? I really think the laundry room would look better with a utility/laundry sink. Hence the main reason the toilet and sink positions aren't switched. So if I want a laundry sink setup:

the toilet needs to be at end of line of that new 3" horizontal line with a closet bend . and then I would need to run 2 3x2 wyes joined to that new 3 inch pipe. Vent wye slightly rotated up from horizontal. One foot from bend for a toilet vent and the next wye for laundry drain (which will be vented in wall behind laundry sink by a san tee. guess i need a cleanout where laundry drain goes into slab (then goes ~horizontal). Apart from having to break more slab.... I don't know if I will have enough clearance under slab to pull this off. Maybe run it horizontal behind wall closer to 3" pipe (but that's a lot of change of directions = bad). Really hate breaking more slab. What about draining laundry sink to side wall and then over to the vertical existing stack? venting would be easier and wouldn't need to break more slab. Would my toilet even need a vent if it's alone on that new 4 ft branch?



Thank you for your patience in advance.
btw- Quebec uses 2005 NPC with a few minor amendments.

[mikeplummer]

going back to your first post....go ahead and call in that plumber...

[Terry]

You do need a vent "between" the toilet and the main line.

Thinking any waste line is going to help with your venting is opposite of how we plumb things.
We have our methods, and with good reasons.

[wrencher]

going back to your first post....go ahead and call in that plumber...

Sounds like my questions have annoyed.

Thanks for the clear "You do need a vent "between" the toilet and the main line" Terry. Was just a misunderstanding.