Vent diagram - does this meet code (see pic)? Vent runs below actual drain
The schematic below should make it clear the configuration I would like to use. Basically, I would like to keep the vent under the floor for a little ways, so it pops up in a better location. I cannot easily move the 2" drain location going down and would rather not go straight up from the location because of flooring issues.
the specific questions are: while the vent pipe is under the floor, if i am sloping at least 1" for every 4' as code requires, is it OK that the vent pipe is lower than the drain height? And second, for this configuration, is it OK to use a vent elbow instead of a sanitary elbow? I heard that vent elbows might not be allowed even though it's for a vent in certain cases, so that is why I ask the second. Unfortunately, I need to use a vent elbow to obtain the sharper turn to keep the vent under the floor...
http://students.washington.edu/jetpe...entdiagram.jpg
Thanks!
Jet