Apparently open vent pipe under my kitchen counter

The following is from my own rental. Not an inspection. Thank you for your help!

Two of the attached photos are from under the sink/countertop in my kitchen. The kitchen sink is in an island/peninsula kinda deal. The other image is the exterior of the building, as you can see it’s very much elevated from the street, so the drain line drops plenty before getting to the street. It’s a 1983 build.

I was foolishly assuming that the open pipe in the wall at the back of a cabinet was an old drain line that was sealed on the other end for some reason and abandoned.

The other day my dishwasher and laundry machine (also located in the kitchen) was running at the same time, and then my girlfriend fed lots of perished food from the fridge down the disposal. Shortly after doing that, she noticed water in the cabinet, near that pipe. you can actually see some of the lettuce that she had just put down the disposal, along with a bunch of roach eggs. Seems like that must be a open vent pipe. But we havnt smelled any sewage fumes in the ~7 months we’ve been here, so there must be a trap somewhere before the sewer connection, right?

Gross as shit, but here’s my question: did this use to be a common way of venting in the 80’s, in situations where the main drain line drops elevation enough to accommodate a trap? Or is this a lardlord renting me a house with a serious health code violation? Or is it both?

No this was not a common way of venting in the 80s. Even in the 80s island venting was a thing. I recommend gluing a clean out on that pipe to seal it up.


Thanks. Landlord has a plumber coming in a couple days. I’m guessing they will tell me they have to put a countertop air admittance valve because there isn’t enough room on that drain line to put an under-sink one, right?

But I’m asking more about my rights as a tenant. This guy’s not my favorite landlord. I told him I’d appreciate a cleaning crew coming to deal with the roach eggs because I don’t have time to clean wastewater spills from his house’s faulty plumbing system, and he has the nerve to tell me that, as the lease says, “pest control inside the unit is our responsibility”. I’m trying hard to not flip out on this guy and start a pissing match, but it also seems like a horrendous health code violation for roach eggs and grey water to spill into my kitchen from the drain system. There is now grey water absorbed into our kitchen cabinets.

I left a message with our local health department, but just curious if anyone has any recommendations for smart next steps, besides repair of the venting issue.

No use in banging your head against the wall with this landlord unless you just want out of the lease. Clean it up, put a bucket under it until the plumber arrives. Start looking for a better apt. :smiley:


Sue the home inspector!!!



hah, yea I was wondering about that. We have received an envelope addressed to my landlord as well as another man and woman with his last name. He also told me today that “that has always been like that and it never happened before”, so i’m wondering if he is the kid of the owners, just managing the unit, and maybe they have always owned it and it’s never been inspected?

yea you’re right. we’re planning on moving again at the end of the lease


Do you understand sarcasm? I was referring to YOU! :wink:


Oh yea right, I admit I didn’t notice the lack of venting after the trap until this happened.

Have you ever seen something like this, Jeff?

I am not Jeff…but last week…

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Honestly, I don’t recall. The majority of my inspections are 50+ years old, half of those are 100+ years old, and have so many 'effed up plumbing issues I can’t recall them all. This one would be more in line with the ‘minor’ issues category I see.


Open pipe under the sink definitely not a common way to vent anytime but around the 80s/90s in my area it was very common to run a vent loop (term?) up behind an island sink. The usual install has since gone to an AAV but I’m guessing what you have is a chopped off vent loop. Someone has definitely screwed something up there as the drain shouldn’t dive before reaching some venting. Probably not the end of the world. If it were my house and it was causing a problem I’d probably just cap it… and wait to see where the problem resurfaced :slight_smile: :slight_smile: