New sink vent in basement

Hi,

I'm finishing my basement and looking for advise on how to vent a new wet bar sink. The nearest existing drain is a 2" vertical pipe from the main floor kitchen sink/disposal/dishwasher. It is individually vented to the roof. I can tie into this existing drain pipe within 3 ' of the new basement sink for it's drain. I assume that I cannot vent the new bar sink without hooking in above the kitchen sink. This would require tear out of walls and/or cabinets in the kitchen, which I really don't want to do.

The only other drain/vent in the basement is the rough in for the basement bath group. It has a 2" vent for the group but is 20 - 25' from the wet bar sink location. Is there a length restriction for a horizontal vent branch from the wet bar to this bathroom group vent? Does the IPC2003 allow additional vents to tie into this bathroom group vent?

There is a floor drain about 10' from where the bar sink will be located in the basement but no dry vent for it so I assume this is not an option.

Is there any way to wet vent the bar sink with the upper level kitchen drain? The wet bar sink will not receive a lot of usage but I'm assuming I can't do this and may need to use an AAV if I'm not willing to tear up walls? Just thought I would check to see if there are any other options. I don't have a big problem with using the AAV since it can be hidden in the bar cabinet and should have easy access.

Thanks,
Matt

AAV might be the easiest way to go. Not sure you'd be allowed to have a wet vent of that length if you just tapped the kitchen drain. I bet you'd have to loop the vent up above the kitchen sink.

There's no length restriction (to my layman's understanding) on horizontal sections of vents. They just have to be downward sloping - either back to the trap or toward the basement fixture group vent jct point. Condensate has to have a place to go.