Need help with adding a new sink in basement

[Marko]

Hi all,

I am hoping you can help a novice when it comes to plumbing. I am in the process of changing my washer and dryer, and have to move the location of the laundry sink. Additionally, I would like to add a new sink in the basement, which will form part of a mini kitchen down the line. Pardon my lack of knowledge on proper terminology.

I am attaching a photo of my current set up. I am wondering if I can do the following:

1. right side - red lines: the drainage on the right is where my old laundry sink was, as you can see by half the trap still there. I am thinking of cutting it back in the wall, installing a 90 degree there and then have it go against the wall, about 20 inches longer than it currently is to where my new laundry sink will be.

2. I would like to add a new kitchen sink, approximately 40 inches away from that vertical drain on the left. I am wondering if i can add a a santi tee there and if this is acceptable and if the new sink will have proper ventilation and drainage and to code.

I really appreciate any help you can all provide. I don't have any issues opening up more drywall if required as this is in the basement furnace area which is half unfinished.

I should add that the pipe that goes into the floor seems to be connected to a floor drain just behind where i took the photo, and that plastic pipe seems to come out into that floor drain, i presume from what I've read this is to ensure that the trap in the floor drain always has water so sewer gases do not come back up.


I did see an old post of Terry's, where he posted the below picture, which i believe to be similar to mine, with the exception that the two vertical pipes are not attached at the top, they come in separately in the ceiling and then connect at the bottom as you can see.

I am wondering if i can do what Terry did here on the left to connect my new sink, and then leave the setup as it currently is for me for the laundry sink and washer, just extend it to the new location.

 

[WorthFlorida]

Not sure of your pipe sizes but here are tables for the maximum distance allowed from drain to venting versus pipe size. One of those two pipes could be a vent. Above, run water at a sink(s) and then feel the pipes below. You should be able to tell which one is a drain. If the washing machine drains into a pipe, it should be a 2" pipe. If it drains into a laundry tub, then 1 1/2" pipe is allowed.
https://inspectapedia.com/plumbing/Plumbing-Vent-Distance-Codes.php#VDist

 

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[Marko]

I attempted to run hot water in my kitchen which is above and to the left but was not able to tell which one of those is the kitchen drain. I did hear some water going but was not 100% sure which it was as I didn’t feel much touching the pipes.

I am wondering if venting is an issue for my proposed set up. Reading the link above, I see that the maximum distance for 1 1/2” piping is 3 and 1/2 feet, which I will be at the maximum amount for the new sink.

I am wondering how I can tell for sure if either of those two vertical pipes are air venting. In case I cannot, would it make sense to put in a AAV to the left of those two pipes close to the new sink. I am not worried about it being visible as this is an unfinished basement area.

What do you all think?

 

[James Henry]

I think if you tear that drywall up higher you will see that the vertical pipe closest to the old sink dirty arm that it is a relief vent and the pipe going into the floor is the drain. run the kitchen sink again but this time press your ear to it... if that is the drain then go outside and look up at the roof over your kitchen and see if their is a vent sticking up.

 

[Marko]

I think if you tear that drywall up higher you will see that the vertical pipe closest to the old sink dirty arm is a relief vent and the pipe going into the floor is the drain. run the kitchen sink again but this time press your ear to it... if that is the drain then go outside and look up at roof over your kitchen and see if their is a vent sticking up.

I will run the water again to see If I can figure out which of those the main floor kitchen sink drains into. I should note, both of the vertical pipes in my original photo go up into the floor joists of the main floor and then make a 90 degree left turn and run horizontally to the left, which is the direction of my kitchen sink. I am not sure if that information helps.

So if I am understanding correctly:

The pipe that the kitchen drains into should be left alone, which is most likely the pipe on the left that goes into the floor.

The pipe on the right is most likely the relief vent. Is this pipe that I should connect the new sink to using a sani tee? Can I connect it above the laundry sink connection? Would that be acceptable?

Thank you.

 

[James Henry]

I do believe the pipe on the right is a vent. why it goes in the floor above I can only guess. I'm not familiar with The Canadian Plumbing Code and you would have to work out the details.

 

[Marko]

So I let the water run in the kitchen and I did confirm that the vertical pipe on the left is where my kitchen sink drains. Therefore, if I understand correctly I should not add another sink to drain into this vertical pipe, is that correct?

Given the right pipe is the venting pipe, and it has the laundry sink and washer draining into it already, am I able to connect a new pipe via sani tee to it, above the current laundry sink connection?

Would this be the correct methodology? I have attached a diagram

 

[James Henry]

This is the logical way I would do it but theirs to many things I don't know about your plumbing and your in Canada so I can't give it 100%.

 

[WorthFlorida]

A vent pipe must go up to the roof for venting. If you use the drain from the sink above, then add an AAV for the new kitchen sink. If you use the vent pipe for the new sink, then add an AAV to the laundry tub on the right. I do not know if NPC for Canada likes wet venting. Someone else may know. The chart in the above attachment does seem off. IPC venting for 1.5” pipe is a maximum of 6ft.

 

[Marko]

A vent pipe must go up to the roof for venting. If you use the drain from the sink above, then add an AAV for the new kitchen sink. If you use the vent pipe for the new sink, then add an AAV to the laundry tub on the right. I do not know if NPC for Canada likes wet venting. Someone else may know. The chart in the above attachment does seem off. IPC venting for 1.5” pipe is a maximum of 6ft.

The pipe for the AAV would be vertical, parallel to the drain or vent I am linking into correct?

How high should the pipe with the AAV go above where I am connecting it?

 

[WorthFlorida]

Instructions that come with the AAV will show the install location. General at the flood level of the fixture. There are hundred of pictures on line that show AAV installation.

IRC
P3114.4Location.
Individual and branch air admittance valves shall be located not less than 4 inches (102 mm) above the horizontal branch drain or fixture drain being vented. Stack-type air admittance valves shall be located not less than 6 inches (152 mm) above the flood level rim of the highest fixture being vented.