I've been plumbing for about 28 years, and I've never seen anything like this. At my church, I took on a drain repair job that got a lot bigger than I expected. In a building that has had a lot of changes and additions, the kitchen drain was tied into a fairly ancient cast iron line that bypassed some newer bathroom plumbing. The decision was made (by others) to tie it into the newer plumbing in the mens's room. We planned to find the kitchen drain in the hallway or kitchen and cut it there. As it turned out, we followed the line into the kitchen expecting to tie into the newer ABS drain pipe there. However, when I cut the ABS pipe, it shattered. So we chased it up a little ways and found a wye where the two sink drains connect, and the pipe was cracked on both inlets of the wye.
We ultimately followed the pipe to the wall at each sink, removing cabinets as necessary, and found that all of the horizontal ABS was bad. Not only did we find radial cracks in the pipe, we found a lot of incipient cracking. It was easy to put a framing hammer claw right through the top of the pipe. The pipe went up at a 45 deg. angle into the walls, and the pipe that was at 45 degrees seemed solid. We ended up replacing 15'+ of horizontal 2" pipe, along with fittings. The fittings also seemed sound.
I'm mystified by this. In an internet search, I found that there was a fair amount of defective ABS pipe manufactured in the second half of the '80's, but the date stamp on this pipe indicates 1997. I've dug up a lot of ABS pipe, and never seen this type of failure. The cracks appear to have started at the top of the pipe and worked their way to the bottom. All of the pipe appeared to have proper fall, and there was no evidence of improper bedding or any other installation errors.
I also can't find a manufacturer's name on the pipe. It's marked "Standard ABS COEX Cellular Core," and then some ASTM standards and a date.
I'm guessing that either massive amounts of boiling water have gone down this pipe, or perhaps some really aggressive drain-cleaning chemicals, but I really don't know.
Anybody seen anything like this?
We ultimately followed the pipe to the wall at each sink, removing cabinets as necessary, and found that all of the horizontal ABS was bad. Not only did we find radial cracks in the pipe, we found a lot of incipient cracking. It was easy to put a framing hammer claw right through the top of the pipe. The pipe went up at a 45 deg. angle into the walls, and the pipe that was at 45 degrees seemed solid. We ended up replacing 15'+ of horizontal 2" pipe, along with fittings. The fittings also seemed sound.
I'm mystified by this. In an internet search, I found that there was a fair amount of defective ABS pipe manufactured in the second half of the '80's, but the date stamp on this pipe indicates 1997. I've dug up a lot of ABS pipe, and never seen this type of failure. The cracks appear to have started at the top of the pipe and worked their way to the bottom. All of the pipe appeared to have proper fall, and there was no evidence of improper bedding or any other installation errors.
I also can't find a manufacturer's name on the pipe. It's marked "Standard ABS COEX Cellular Core," and then some ASTM standards and a date.
I'm guessing that either massive amounts of boiling water have gone down this pipe, or perhaps some really aggressive drain-cleaning chemicals, but I really don't know.
Anybody seen anything like this?
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