No Sewer Vent?

The drain is connected to a second drain by looping up by the faucet. I don’t see how tis can be counted as a p trap as I see no venting. Can someone tell me otherwise, I have not seen anything like this before. Thanks in advance. Karl:shock:

kit sink 9.jpg

kit sink 9.jpg

kit sink 4.jpg

Are you sure it’s not like this?

Island Vent (standard method)

Possibly, but I did not see the vent connection in your diagram. Here are crawl pics of same piping. If the vent connection is not higher than the pipe connection won’t water stop the venting?:neutral:

crawl 7.jpg

crawl 2.jpg

I can see how your diagam works, they may have tried that since this is a log home. Wouldn’t a manufacured stlye mechanical vent be easier?


It’s hard to inspect from pics.
IMO you have enoughtot call out evaluation by a specialist.

There is a solvent weld ABS fitting to a PVC wye shown it your first and second photos. A special solvent that is compatable with both ABS an dPVC is required for this and generally only one transition is allow in a system.

In photo 4 you also have a pvc transitioning to some type of soft banded fitting, where does that end up?

Where does the wye fitting in the basement crawl photo go to?

Sorry for all the questions but it might be best to defer for this one.

Yes a “Studor” vent would be easier if allowed in your area.

Thanks much, I wasn’t expecting a thorough inspection from pics. you have given me all the tools. The diagram was perfect. I love this association because members are always willing to help since none of us have seen eveything. thanks again, Karl

I found this interesting item today. It is the house sewer vent for a septic system in a very small town. The house is over 100 years old and the drain system in the house works like a charm. The house only has 1 bathroom so I had all faucets on (including the tub) and then flushed expecting an overload. Surprise!!! No problem, even adding the kitchen drain.
I don’t think it would pass any kind of a code, but how should it be written up?
My only beef with it is its location during the winter for snow buildup as it is only a few inches off the ground.
By the way, there aren’t any openings within 10 feet in any direction and I didn’t smell it at all during the inspection.


The whole set up is called a loop vent by most older plumbers. They usually work, but not sure if they are legal anymore. I haven’t seen one for a long time. Only approved in island sinks. Used to be used in Bars or Taverns all the time.

Terry, without more information couldn’t say, but septic vents are acceptable, although that one seems to be a little close to the house. Might do some more research before you write it up.

“Island Fixture Vent” is the term used out here.

They are perfectly acceptable (when installed correctly) and used in all modern construction in CA. They are allowed by most model codes (as far as I am aware), but are allowed only for use with sinks. See IRC 3112.1 and UPC 909.0

I wonder if there is a one-way-valve in that elbow, a simple flap held down by gravity? It would be there to help the flow, but force the methane out another way. JAT. :p:idea:

A bunch of plumbers are using AAV’s instead.