I have the following situation for a WC (see pics)... the WC is dropping to a closet bend then going down for around 1ft at 45-deg... I can vent it either on the 45-deg drop (so about 10" below WC) or after it levels out (around 14" drop from the WC). I cannot vent before dropping down b/c there is a chimney in the way and I must turn and drop right away.
Normally, for a fixture the vent take-off must be above the p-trap weir; in a WC of course that is not possible... but I am wondering what the acceptable limits are... or how far can I drop below WC closet flange before venting?
So am I ok with alternative #1 or #2 (see pics) or must I do something else?