Flushing a toilet down a 2" drain pipe

[cmac2012]

I hope you guys don't take a poll and decide to run me out of here so as not to tarnish the reputation of this place, but ... this is actually a serious question. I have a nice new client, well, about a year into working on their stuff, they bought a loft in an older converted SF building about 6 months ago. The building is interesting, about half of the units are for dwelling, the other half more for office. Their first unit was a full tilt apartment. Their second is an office unit just across the hallway. This unit has a washer and dryer with 220 outlet, hot and cold water of course and a 2 inch drain.

The lady of the house wants to turn the office into half living unit, their college age son comes to visit and they'd like a place for him to have his own room, which just isn't there in the main unit. Her hope is to have a toilet that can be used for liquids only, good old number one. He expressed displeasure with needing to put on enough clothes to go across the hallway (all resident access hallway) to use the privvy at night.

They assure me that no solids would ever be introduced into that toilet. Putting in a 3 inch drain in this unit is out of the question. I'm not sure this would pass the HOA rules, no scratch that, it would not get approval. The room is long, maybe 50', about 10' wide. She wants a wall put in about 8 or 10 feet away from the wall that has the washer/dryer and where the new small water closet would be put. I'll sheet rock the outside surface at least, we have leftover paint, can make it look like part of the room. This would give a camouflaged effect for the changes which should not be seen by people walking the hallway when the door is open.

My thought is to put the toilet on a 15 inch platform, the door would open to a 7.5 inch step, one more up to the throne. That way I'd only have to go into the wall to attach to the laundry drain, opening the floor would be a nightmare.

Putting aside such points as "am I out of my mind," my immediate concern is if the 2 inch pipe would accept a flush without complaining. I get that those ususally pass through a 2" opening or slightly bigger at the bottom but then there's normally room in the 3" pipe to let the water then move at the speed it wants to move. Another issue is the trap on the laundry drain. Those are often near the bottom, would need to tie in below that of course.

 

[SHEPLMBR]

put in a urinal. That would ensure no solids.

 

[Jeff Handy]

Urinal is a great idea.

Or, you can install a macerating toilet, it chops everything up to mush, uses an electric motor and pump to spin sharp blades chewing up paper and poop, and some can pump the discharge through as small as a 3/4 inch pipe.

They can also pump the discharge uphill at least about six feet, so you probably would not need a raised platform.
Some can also accept drain water from a sink or shower.

They still need a vent, but maybe an AAV would be enough.

 

[breplum]

Forget a conventional toilet.
A waterless urinal would be a really good choice. I've put in lots and they are great as long as they are cleaned and fluid replaced as needed.

Regular urinal with flushometer will tax the water supply slightly and piping in the building because the supply is not really sized for that, but on real-use basis it would work if not a lot of activity in the building.
You would have to do load calcs for the water system.
But really, a Saniflo macerating setup would work as well, and allow for emergencies to be met. I just would guess that the joyful wonderfulness dealing with both the HOA and permits, if it is in City and County of S.F., could be a hurdle. I never tried to pull a permit for one in the city. And most other cities I've dealt with don't approve of them.

 

[Jeff Handy]

https://www.amazon.com/Medline-Portable-Microban-Antimicrobial-Protection/dp/B07H7MQWPW

 

[Jeff Handy]

 

[Jim Jensen]

https://www.amazon.com/Medline-Portable-Microban-Antimicrobial-Protection/dp/B07H7MQWPW

ok, that is WHAT she and he really will need to/ have to settle for......welcome to living in commieFORNIA..... ha ha

 

[cmac2012]

I worked with a good ol' boy carpenter from Norf Carolina on a big job in '04 in Atherton, a mega bucks enclave in these parts. Born in Florida it was his first time west of the Mississippi. His wife had family in the area and needed to care for one of them. One day he told me, "you know, I've been hearing all my life how loopy and liberal California is, especially the Bay Area, and now that I'm here, it seems like just about everywhere else."

View attachment 25031

Thanks for all the advice, not sure yet what I/we are going to do. I think I know how I'm going to vent it. I'll know if it will work when I open the wall. I know she absolutely wants a toilet. She wants to be able to use it as a guest room when people visit and women might want to pee at night. Like she was telling me: "nobody chits at night." Usually true. I told her we'd need to put up a large sign, or maybe two of them:

NO $HIT!

 

[Jeff Handy]

Guests will go to the “pee only” toilet, and suddenly those five spicy burritos from lunch will kick in, and they will drop a huge steaming load.

Prepare for that, no matter what your warning sign says.

 

[havasu]

Make sure the sign also states no toilet paper can be used and a drip-dry method must be practiced.

 

[cmac2012]

Guests will go to the “pee only” toilet, and suddenly those five spicy burritos from lunch will kick in, and they will drop a huge steaming load.

Prepare for that, no matter what your warning sign says.

I should perhaps have my head examined. OTOH, this lady has been giving me a LOT of business - she's an interior designer, I'm building her some groovy stuff in this loft. She wants to show it to clients and then say, 'I can hire this contractor for you.' I have a couple of unusual ideas for insurance on ze poopin' angle. I'll look into it more before I describe them.

 

[cmac2012]

Make sure the sign also states no toilet paper can be used and a drip-dry method must be practiced.

Excellent point. I'll need to stress that with her.

She's big on bidets. Perhpas there'd be no paper in there, just some sort of cheapo bidet, even just the hand held sprayer works pretty well.

 

[cmac2012]

Guests will go to the “pee only” toilet, and suddenly those five spicy burritos from lunch will kick in, and they will drop a huge steaming load.

Prepare for that, no matter what your warning sign says.

I'm leaning more and more to the macerating setup. Just less stress.

 

[Jeff Handy]

A macerating toilet works well, but can only handle pee, poop, and toilet paper.
Similar to a sink disposal, but with a pump to move the mush downstream.

Anything else will jam it up.
Including tampons, toilet wipes, paper towels, etc

So a sign should be posted above it.

 

[cmac2012]

I think I can get them to stick to that much. I have to wonder what happens when you have to take it apart and service it. Oh well, I've snaked sewers so it's not like I'm a hothouse flower.

 

[Jeff Handy]

I have taken them apart, almost no smell.

Just flush the toilet a few times first, with just water.

To clear out the tank, and the discharge line.

Otherwise some poop water can run back out of the iffy rubber check valve.

You should also install a ball valve on the discharge line.

Needs a gfci outlet for safety.

The Saniflo pump tank plastic cover can be hard to get back on, after a few years.
Even with a new gasket.
VERY tough to wrestle it on sometimes.

I just make my own new gasket with self adhesive closed cell foam tape from HD.
Easy peasy and no leaks, no torture trying to get that lid back over the manufacturer’s tank gasket.