to vent or not to vent kitchen sink?

[remodelbob]

I had a plumber buddy by my project (complete remodel of house, relocating all plumbing in kitchen and master bath) the other day and he said if I run 2" that I don't need to vent my kitchen sinks (one main and one prep).

that sounds wrong to me, but it sure makes my life a whole heck of a lot easier if I don't have to as the sinks are directly below windows (and a stupid number of 2x6's that the window guys put in--two extra on either side because the row of windows was not level, so rather than pulling out the wrong trimmer studs, they just added more...)

so my questions are:
1 - is this true?
2 - do i need an AAV?
3 - what kind of fitting should i use? I was thinking a san-t and then capping off the top just in case I ever had to add a vent
4 - what size should I come out of the wall with? 1.5" or 2"?

thanks!

[master plumber mark]

that is why they sell the AAvs

if you run 2 inch all the way up under the sink
and then install the AAv inside the cabinet as high as
possible, above the drain, it will work fine
for probably 40 years..

they are literally used about everywhere you cant
chop the living hell out of the home...

you need to make the aavs accssable under the sink for
long down the road .....


their are some regions and plumbers that frown on useing
them but they are still sold in jsut about every hardware store
in the USA....

[Cass]

1.5" is in 99% of the sinks in America but if you can run 2" so much the better.

You should go from the trap directly to a T with the AAV as high above as possible.

That would be the best set up for the AAV.