: If plumbed correctly, there is no reason to have the WC downstream from a tub, shower or lav.

: Deb
: The Pipewench

I have two alternatives I was considering.

#1: Using Air Admittance Valves on all three
fixtures eliminating conventional venting.

#2: There is a vent above the area where the bath
will be located. Unfortunately (?) it is
only 1 1/2 in diameter. It presently vents
the equivalent of 7 fixture units including
a water closet in that count.

I thought about shooting a new two inch
vent pipe close to it to the attic (one
story home and capthat with an Air
admittance valve avoiding another cut in
the roof. The stack that goes into the roof
is 1 1/2 to 3 inches. It would be easier to
do it as I propose.

Would either of these methods work? Being Plumbed
correctly.