Washer and kitchen sink/dishwasher drain in Basement

[Mayfield571]

I am trying to help my parents add an in-law suite to their basement to include a kitchenette and a washer/dryer. There is a 3" drain running through the wall that has a bathroom from the first floor running through it. I have drawn a quick diagram of what we are thinking will work for this scenario. Could anyone confirm if this is sufficient or if there are any issues. I'm not crazy about having to use 2 AAV's but trying to run a vent pipe from this location would be a nightmare. Thanks in advance.

 

[Terry]

The washer needs venting on the trap arm, not below it. What you have drawn in green would siphon the trap. The venting is there to prevent that.

 

[Sponsor]

 

[Mayfield571]

Ah, I've moved it in the below drawing. Everything else look okay?

 

[wwhitney]

2" for the kitchen sink is preferred, although IPC allows 1-1/2".

Under the IPC, the laundry standpipe drain is supposed to increase to 3" as soon as another drain joins it. So it would be better to connect the washer and kitchen sink drains separately to the 3" stack.

Cheers, Wayne