My sewer pipe is cast iron and comes through the basement wall about
24" off of the floor. There is a Y fitting and elbow to turn the pipe
90deg and run it along the wall. The straight portion of the Y has a
Can I put in a slop sink and using appropriate fittings run the P trap
into the Y where the cleanout plug currently resides?
My obvious concern is getting backup of other waste water into the
slop sink. About 4' upstream of the Y is a sanitary T running to a
1st floor toilet. Right below the toilet flange is a 2" wet vent that
goes to two first floor sinks (a lav and a slop sink for the washer).
The main continues around the basment walls to the back of the house
for the kitchen and two second floor full baths (30' upstream of the
My plan is to move the 1st floor slop sink along with the washer into
the basement. The only thing left on the wet vent at the first toilet
would be the sink in the 1st floor half bath. Currently no drainage
problems at all with 2 1/2 baths, DW, and washer.
A check valve between the sink trap and the rest of the system could
prevent anything from backing up into the sink.
However, my brain might not be working this morning. If the existing
cleanout is 24" off of the floor, how were you planning on getting the
slop sink waste up to that cleanout?
Slop sinks are usually pretty deep so wouldn't the outlet of the trap
be well below 24" from the floor?
A check valve might not prevent sewer water from backing up into the
sink. I've had that arrangement and what always happens is that the
backup occurs fairly slow. The increase is so slow that a small
amount leaks around the flap to the sink side. This continues and
allows the sink to fill. Now, once you quickly empty the sink, you
have a nice pressure differential between the 2 sides of the flap,
and the flap is held tightly against its seat. When I discovered a
sink full of water and it was about 5" from the top, I took a garden
hose from the sump pit to the sink. I started running water from
the faucet into the garden hose, and once filled, plunged it into
the sink to start a siphon. Once the water was drained, no more
came in and yes, it continued to pour rain outside for some time. I
ended up putting a 1 1/2" plastic ball valve in the drain line. Of
course, you have to be there to turn it.
I guess that's why the "backflow preventor, later installed by my
village sewer department, was not a simple check valve. It was
actually a flap controlled by a mechanical float. When the float
started to go up in the unit, indicating a backup condition, it
would mechanically, close the flap. Further backup would then press
the flap tightly against the seat. Any water coming from the house
would push another valve open and drain into a pit beneath the unit,
where an ejector would force the house sewer water into the now
backing up sewer. This unit was installed in a 3' diameter x 9'
deep manhole in my front lawn. It was then covered with a square
cover holding soil and grass, so it was almost invisible. I saw the
bill from the installer .... it cost the Village about $5K to
install. And, that was about 10 years ago. But, I digress.
A washing machine in a basement is never a good idea. If I proposed
that to SWMBO it would be as welcome as a turd in the churn. Dragging
loads of laundry up and down the stairs is OK for college kids and
other under 20's, but in a family situation it truly sucks. Many
families these days have laundry facilities on the second floor of
well planned houses. Rethink your project, or better get some
professional design help if you feel you must do it.
I remember reading that a vent is not needed if you are within a
certain distance to an underground pipe.
I think the existing wet vent that is right below the nearest toilet
flange would prevent the trap in the new basement sink from
siphoning. If not I can run a vent for the trap up and tie it into
the vent above the sink on the 1st floor.
I would connect a 2" cast iron pipe into your lateral with a trap that has
about a 2' vertical pipe it end. I would would then get a pump such as
Little Giant 506065 http://www.buyplumbing.net/?pg=pd&_iP6065 and run the
sink drain through that pump to the verticle pipe.
Our laundry room is in the basement and we have a sink there next to
washer. I just went down there to take a look. Basically same as what
you are trying to do. When house was built builder finished the basement.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.