View Full Version : Basement sink drainage
rgauthier20420
Jan 14, 2014, 03:18 PM
Ok guys, I've got a question for any plumbers (or someone with the knowledge) in the group. I'm finishing my basement and am wanting to put a wet bar in. I've got an open floor drain the condensate runs into already from the heating unit (or AC unit), and I was thinking of just running a drainage line from the sink to that same open floor drain above the slab. The drain itself has a P trap and then meets up with the bathroom sewage lines and then to an ejector pit so no worries on the removal end. I understand it's not code, but that's not the question here. I'm wondering if it won't drain properly or will it drain just fine.
ma0641
Jan 14, 2014, 03:41 PM
Since the condensate apparently drains properly, the bar sink should too. It should not be a permanent solution.
speedball1
Jan 14, 2014, 04:20 PM
I was thinking of just running a drainage line from the sink to that same open floor drain above the slab.
I was cool with that. It is called a indirect waist and a indirect waist does not require a trap.
But then you said,
The drain itself has a P trap and then meets up with the bathroom sewage li hundred nes and then to an ejector pit
So now my question is this, do you plan on running an indirect drain to the floor drain or tying into a drainage line going to the ejector pit? In that case you will need both a "P" trap and a vent. So which way did you decide? Back to you, Tom
rgauthier20420
Jan 15, 2014, 07:12 AM
speedball1,
I will be running an indirect drain into the floor drain. The plan is to simply attach a PVC drainage pipe to the sink and run it directly into the floor drain. What I mean by into, is that the pipe will just be sitting in the open floor drain with a 90 degree elbow to hold it in place. I will not be hard plumbing anything into any existing drainage pipes under the concrete slab.
When I mentioned the P trap, I was really just guessing at what type of piping the floor drain has and not the sink I'm planning on installing. The reason I say I think the floor drain has a P trap is that there is always water sitting in to prevent sewage gases from escaping. The floor drain does drain directly into a sewage line that is then all run into an ejector pit. But like I said, the actual drain pipe that will be running off the sink will be above the slab and just slightly poking into the floor drain opening.
Let me know if this helps. I've gotten responses from a couple other friends that have a similar setup and it works fine. I like to get the feedback of the pros when possible though. Thanks.
massplumber2008
Jan 15, 2014, 08:00 AM
Hi...
Plumbing code will want you to connect this, "indirectly". That means leaving the sink drain pipe so it is a minimum of 1.5" above the floor drain. Although this could lead to a little splash at the floor drain it can also NOT lead to any backflow condition up the sink drain pipe....a good thing, especially at a wet bar!
Further, many codes will also require a mechanical vent (AAV) if the sink drain pipe is more than 5 feet from the floor drain. Here, you install the AAV under the sink so it is "readily accessible" should it need to be changed out and the PTRAP at the sink and then run the drain over to the floor drain as required.
That should be all you need...;)
Mark
rgauthier20420
Jan 15, 2014, 08:06 AM
Thanks for the additional explanation master! That's very helpful, and it makes me feel a little better about the installation. The drain will be within 5" of the drain, so I'm thinking I'm good to go.
Just happy I don't have to go busting up anymore concrete. Roughed in a full bathroom already down there and I did the labor before a plumber came in. I wish breaking up the concrete was as easy as filling it back in...
massplumber2008
Jan 15, 2014, 08:22 AM
Hang the pipe well and you should be all set!
Good luck!
speedball1
Jan 15, 2014, 12:53 PM
AAV. "P" trap for a indirect waste ? My code does not require either a trap or a vent on an indirect waist. What is the trap to vent? It is just a pipe open on both ends. I realize that different areas have different codes but I don't see much sense in trapping or venting a indirect waist that should be open on both ends.
So, educate me Mark, Stay warm, Tom
massplumber2008
Jan 15, 2014, 03:25 PM
Hi Tom
All codes require a Ptrap and a vent to a fixture after what, 3 feet or so. In most states, the same applies to indirect wastes in that scum can still build up and smell/contaminate food and ice, etc., that might be left in a sink (especially at a wet bar), so installing a ptrap will keep odors from the dirty indirect drain pipe out of the sink and the vent will make the drain waste self-scouring" like any other vent does!
I know it has probably been awhile since you updated with the newer codes, but heck, even your FL code calls for a PTRAP on all (section 802.2) "indirect waste piping that exceeds 2 ft. in developed length horizontally, or 4 ft. in total developed length". I bet if the pipe exceeds 5-15' then the indirect drain needs to be vented, too (just didn't want to read your entire code book...LOL).
Chat soon!