I'd like to get some comments on four venting options for a kitchen island sink. There is a hollow column adjacent to the island where a vent from the basement sink goes up to connect to the vent stack in the attic.
The sketch below marked as Original Plan has a vent from the island sink P-trap directly connecting to the vent line from the basement. It connects to the vent line below the flood line of the sink, but should the drain line plug, the water would simply back up and flow down the vent line. This seems to me to be an acceptable design, although perhaps not to code.
In my jurisdiction, I can use an AAV, although I really don't like those when there is a batter alternative.
Then there is the classic loop vent.
And then I thought with the vent line right there, I could connect the vent side of the loop vent to the vent line from the basement.
I'm still favoring the Original Plan. I have a great relationship with the city inspector as a Professional Engineer and have provided him a lot of information on various unique design issues. He respects my opinion and I believe he will allow me to install what I feel is the best approach, per code or not.
But I thought I would through this out there for comments and recommendations from you professional plumbers.
The loop lines would be 2" if I used that design, and all the straight vent lines are 1 1/2".
So, what do you think and thanks in advance for your comments.
The sketch below marked as Original Plan has a vent from the island sink P-trap directly connecting to the vent line from the basement. It connects to the vent line below the flood line of the sink, but should the drain line plug, the water would simply back up and flow down the vent line. This seems to me to be an acceptable design, although perhaps not to code.
In my jurisdiction, I can use an AAV, although I really don't like those when there is a batter alternative.
Then there is the classic loop vent.
And then I thought with the vent line right there, I could connect the vent side of the loop vent to the vent line from the basement.
I'm still favoring the Original Plan. I have a great relationship with the city inspector as a Professional Engineer and have provided him a lot of information on various unique design issues. He respects my opinion and I believe he will allow me to install what I feel is the best approach, per code or not.
But I thought I would through this out there for comments and recommendations from you professional plumbers.
The loop lines would be 2" if I used that design, and all the straight vent lines are 1 1/2".
So, what do you think and thanks in advance for your comments.