In my fairly new town house, the ABS plastic drainage pipe from the upstairs baths and laundry is located just above the living-room and dining-room ceilings, and the flush of a toilet sounds like a deluge. Obviously, this is not pleasant to hear while I have dinner guests.
Because of remodeling, I have removed the ceiling, and the pipes are exposed. I am considering wrapping the ABS with several layers of fabric soaked in something like concrete, much like a broken arm or leg is wrapped with gauze soaked in plaster of paris to make a cast. I’m hoping this will increase the pipe’s mass and its ability to contain noise.
Have you any experience with something like this? How effective do you think it would be, and can you suggest other or additional noise-containment steps?
Jerry M. Mitchell, Sunnyvale, CA
Peter Hemp, a plumbing contractor in Albany, California, replies: Unfortunately, insulating the existing plastic pipe won’t be too effective. In the past I’ve tried to solve this problem for customers but haven’t found any insulating method or material that’s really satisfactory. Of the materials tested, I found that heavy, commercial rubber carpet padding wrapped around the pipe and secured with nylon cable straps is the most effective.
You’ve got the ceiling open, so the best thing to do would be to replace the accessible ABS pipe with cast iron. If I were you, I would find out which plumber did that despicable deed and let him know in the frankest terms that a complaint will be filed with the contractor’s board unless he comes back to rectify the problem.