I'm trying to add a sink next to an existing bathroom. Sink will be probably 3 feet from shower vent pipe. Floor is a concrete slab so all existing drains are underneath. I'd like to minimize busting thru concrete. The picture below is a pretty good representation of the existing piping, except for the pipe below grade that are probably running horizontally.
Can a sink drain/vent into a nearby shower vent pipe (e.g. connection in red on the picture)?
If this is not allowed, what's the best solution here?
Best Answer
I wanted a utility sink installed on the common wall of our garage and house. There was a vertical vent inside the wall near a bathroom and near the washer/dryer alcove. The plumber plumbed the drain into that vent saying that this was allowed by code if done in the right way. I didn't understand what would make it code compliant and would make it work properly, but he put it in and it has worked for 20 years.