I'm moving my kitchen sink over about 5'. I don't want to use the
existing wall drain as running the pipe over does not provide enough
drop, so I've cut the iron drain below and installed a no hub to
transition to PVC.
The way I see this is that I will put in a tee (in the basement) so
that the vent is connected as before but the sink will drain in from the
side. The sink itself will drain down through the floor and then run
over the 5' to the tee.
Am I missing something?
It's a double sink with a GD. I thought I would run the non GD
(garbage disposal) straight down. Do I need a baffled tee for the GD
connection? No DW. One trap just below the tee.
Can't find the UPC online, although I'm not sure I would understand
it. Fixing old plumbing (20's) is quite an art!
Got the floor fixed and the new flooring down, the plaster is fixed
and painted and next up is cutting up and making the base cabinets. It's
been a job!
There is code about how far you can run before venting based on darin
pipe diameter. If you want to play it safe you could install an
inside auto vent right under the sink.
Google "air admittance valve"
Assuming your existing vent/drain is 2" in the wall, why can't you
extend both the vent and drain over five feet to the new location?
That's what I did. I cut the vent, put a no hub coupling and attached
pvc ran five feet over, then drops down with a 2" TEE, with one part
sticking out of the wall for the sink drain, the other part of the TEE
continues down, then re-connects to another no-hub to the existing
drain line five feet over.
If you run the drain pipe down, when water runs down the drain the trap
will siphon - leaving no water in the trap. You will then get sewer gas
The pipe needs to run horizontal with a vent out the top 'nearby' to
supply air to eliminate siphons. If you just ran across to the original
location, 5' is probably way too far.
The horizontal part of the vent may have to be somewhat above the top of
the trap - I don't know. Else sounds practical to me. Could run the
drain down through the floor, as in the Jeff's post, if that is easier.
An "air admittance valve", if I remember right, is an air check valve
that replaces the vent line. Not kosher here, Jeff could check where he is.
Could try a book on plumbing from the library. Would be a good idea to
review plan with an inspector, perhaps anonymously, if possible. Are
there any actual plumbers in the newsgroup?
I can't quite tell from your description exactly what you plan to do.
But here are the requirements you need to meet, as I recall from
memory (so I might not be 100% correct):
Trap under the kitchen sink above the floor (you can't run the sink
vertical sink tail piece into the basement).
Trap arm (horizontal run out of the trap) of limited length (see the
UPC for the exact length, but certainly 2' to get into the wall is OK).
At the end of the trap arm, you need a sanitary tee, with the drain
outlet downward and taking your vent line from the top.
On the drain side of the sanitary tee, you can go vertical to
horizontal to vertical all you want to reach an existing drain, but
you need to use a long sweep 90 when going from vertical to
On the vent side of the sanitary tee, your vent needs to rise to (I
think) 6" above the flood level of the sink before turning
horizontally. If you can't achieve this, then I think you can still
do it if you plumb the portion below the specified height as if it
were an extension of the drain line--i.e. maintain proper slope
towards the drain, no vent 90s, and long turn 90s where the vent turns
from horizontal to vertical (where if it were a drain the pipe turns
from vertical to horizontal). The point of this rule is to ensure
that if the drain line gets clogged and water backs up and overflows
the sink, that no water gets trapped in the vent line, potentially
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.