aav install

[Unregistered]

Does it matter where in the branch drain pipe going to the main drain pipe I place the aav as long as it is the proper dfu rating and it is at least 6 inches above the hightes flood plain fixture. I thought I read somewhere the toilet must be the last unit attatched or was it the first or does it matter.
Was planning the add 2 bathrooms (#1) toilet, shower/tub vanity and (#2) shower, pedestal sink and toilet with a kithchen sink in adjoining room attatched to this. Oatley makes a 20 dfu, would this work connecting all of these to one aav. I have 2 vents going to roof but see know way of connecting these basement fixtures to exiting vents. thanks

[mdshunk]

The only apparent IRC requirement on placement of the air admittance valve ('studor vent' to others) is that it be accessable and above the flood level.