1st post here. Looking to get some feedback about this possible DWV system for my bathroom renovation. Was going to wet vent the shower up the lavatory vent. and have 2" stack go to the attic. Shower drain line 2" will drain into the toilet drain line 3" but have a have the shower vent in line between the shower drain and toilet drain. Vent the the toilet up to the attic with 2" pipe and tie into the other vent before exiting the roof. Please post and potential problems you see here.
Also would a whole house AAV work instead of exiting through the roof.
Thanks in advance for your thoughts,
New Haven Ct