I’m remodeling two bathrooms for a customer and in the process I am installing new toilets that have more flushing power than their old ones that were original to their 40 year old home. After I installed one toilet I got a call from the owners saying that the contents from that toilet were being flushed into the adjacent bathroom’s toilet. I went over to their home to do a temporary fix and then opened the ceiling the next morning. I was surprised that the two toilets emptied into the same drain without any offset. The new, more powerful, toilet’s flush path was directly to the other toilet. That would never pass code today. See photos below for the fix.
