: We have 2 upstairs bathrooms whose drains go into one sewer line that exits the house. We've had 5-6 clogged drain backups since we bought this 35 year old house 2 years ago. The 3" drain is copper, runs horizontally for a couple of feet to a 90 degree horizontal turn continuing to the edge of the wall; at that edge is a second 90 degree connect to a cast iron pipe, which goes down the wall of the house.
: We've had drain roter-rooted each time, and ceiling repair twice. This time we've left the sheetrock off to investigate (thus know how pipes connect). Our plumber believes that horizontal 90 degree turn is the culprit...he and his consulting friend believe a 90 degree turn so close to the source of the sewage is a bad idea...that the turns should be split into 2 45's, for example. He thinks the sewage is hitting that sharp turn and not flowing clearly out.
: Does that make sense? We are considering re-plumbing. (He's camera-ed, pressure cleaned--says both devices are having trouble with number of turns required).
Without see the bends and how they are graded, it would be hard to guess. From what you say though, I would be surprised that one 90 bend would cause so much problems. It may be cheaper to install a "pressure assist" toilet to help clean the lines. Most of them have a drain line carry of aprox 60 feet. Terry