Anyone here familiar with wet venting and loop venting?
Remodeling my bathroom and I switched to a wall mounted sink. The previous drain went into the wall on the side, which was vented. I want to run the P trap straight back into the wall with the supply lines and tie it into the 3" toilet drain which is a wet vent.
Unfortunately, it is generally forbidden by most building codes to tie into a wet vent if you are downstream of the toilet drain. Can I disregard this? I have pulled no permits and have no compelling reason to meet code if it is not based on sound reasoning.
Consider the following from Plumbing and Mechanical magazine:
"The most commonly added requirement is that the water closet must be the last fixture in the wet-vented system. That makes it difficult for a double bathroom group wet vent. The two water closets would have to tie in together.
Actually, there is no technical justification for making the water closet the last fixture. Thousands of wet-vented systems are working where the water closet is not the last fixture. Someone assumed the water closet is a blow-out fixture that blasts through the pipe, sucking everything with it. Well, that isn’t true."
So if you do believe this is a legitimate rule, is this still bad to tie into this drain if I loop vent (or AAV) my sink drain?