Quick question: is it legit to run the waste line from a kitchen sink
under the cabinets but above the floor ? I wish to hook into
the old line which is in the corner of the room, the new sink
wants to be in the middle of the same wall. I would like
to keep the pipe above floor to maintain head room in
the basement. Joists are perpendicular to the direction of
the drain.
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Replies
Onder- here's a non-plumber answer for you as long as no one else is there. I would say the trap would be the problem here. I've never seen a situation where the trap wasn't accessable in the sink base cabinet- that puts the drain line above and running inside (at the back of course) the abutting cabinets, not under them.
No, you would have to have the trap as normal. Then from the trap it has to run a "short distance" horizontally. I think a min of 6-8" but you can find that in http://www.codecheck.com and then click on sample.Then you can drop down and run the line horizontally at a lower level. This is basically the same as if it went into the wall and then dropped down to run in the basement ceiling.The only problem is venting. Might need to use an air admitance vavle.
You can run the waste pipe in the toe-kick space under the cab carcass as long as the run isn't too long. Being as a standard toekick is 3½", you don't have a lot of height to lose to maintain the drainage slope.
You may find the hardest part is getting the pipe turned 90 degrees inside the height you've got to work with under there. I normally go to 2" right out of the tailpiece, but you won't have room for that in this application. An Ipex 27121 1½"x1½" 90 in ABS is 3¼" high; they make a tighter one (27111) which is only 3" high but it's got a square corner inside. That doesn't strike me as the best idea for a kitchen drain, especially if you're going to tie the DW discharge into that same line.
It might be easier to run the drain inside the cabinet itself, up against the back of the carcass and as much out of the way as possible, then dive down straight through the floor when you over the existing connection.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Thanks for the input all. I know I need the quarter inch to the foot for the slope.
Six feet would be great Ill have to check on how far you can be from
the vent.
It may well be that dropping down through the floor will be required.
10' for 2". I've got a similar deal under my laundry sink - it sits on a toe-kick base that offsets the drain 3', and raises the sink 4"
Forrest
you could block the cabs off the wall & go with a deeper top......
could block the cabs off the wall & go with a deeper top
Kind of what I was thinking, too; except my thought was to get some 21" deep, standard base-height cabinets for that one side of the kitchen--if only to not have to cut all those holes in the endpanels one after another after another after another . . .
The vent will be key, I'm thinking to this. It's either going to have to have a loop vent or an AAV to be legal. After that, running the line down the wall, exposed (to be covered up by cabinets) seems simpler than trying to get it down to the toe kick.
Unless the DW is on the drain side of the sink--then all bets are off <G>.Occupational hazard of my occupation not being around (sorry Bubba)
I think the vent might not be a big problem...kitchen sink vents are often offset from the drain (windows above sink, often), & I think code is fairly generous with the distance allowed....