the red arrow is the 3 in. drain line under the floor. this is an old mobile home on a basement. i ripped out the vapor barrier under it. i cannot run venting through the ceiling and roof.
my question is, how could i vent this? vent size going through wall? tie them in together before doing so? UPC compliant?
JUst an FYI.....
the venting needs to go through the outside wall behind the WC and lav.
the toilet flushes terrible by the way. and the drain lines i am redoing because when i pulled the vapor barrier down it was easy to see which way things were actually sloping (back to the shower from a san-t in the main 3 inch line). the sink drains to a 2 way san-t immediately under the toilet flange which i think would be considered the vent for the WC however that section to the sink also slopes the wrong way. thanks so much!!