Internachi certified professional inspector
I had an incident recently where our kitchen sink was suddenly not draining. Before this event, we had no issues whatsoever when using the faucet. I tried the usual methods: snaking both sides of the sink, using drain cleaner, and pouring hot, soapy water down the drain. Nothing seemed to work, and the slow drain continued.
Eventually it became clear that the entire drain system visible under the sink would have to be completely removed and replaced, as acrylonitrile butadiene styrene (aka ABS) is not generally feasible to repair. Upon dismantling the plumbing I quickly found out what the problem was. I was going to post detailed pictures of the issue, but I want you to hold onto your lunch today.
Essentially, the top of this p trap (where the black pipe meets the part with white paint) was nearly completely clogged with a disgusting brown sludge known as a fatberg. This should not happen under normal operation, so I went to investigate further. I quickly discovered that the previous owners of our home had washed what appeared to be 2 long bamboo sticks down the sink. Over time, these sticks grabbed onto food and other particles and led to a reduction in water velocity going to the main drain line. As a direct result, the sludge was not forced down to the main line and slowly built up over time.
Much like Radon and Asbestos, being careless about putting items that don’t belong down the sink, such as grease or sticks, isn't likely to cause any short-term issues. However, the cumulative effects can come years down the road, often with little to no warning. If you were to tell me the week before I took the drain apart that it was full of sludge, I would not believe you, but the evidence was clear as it was obvious why our sink was not draining properly.
The plus side is that we now have a clean slate, where we can be careful not to have this incident repeat. While it wasn’t an expensive fix (about $100 total), it was not fun having to spend a Monday evening (and into Tuesday morning) making this emergency repair, all while having a counter full of dirty dishes.
Many homeowners believe that small, careless decisions or neglect of their home won’t make much difference to them in the long run. This may be true during their time of ownership of the home, however it will eventually result in issues. Our clogged sink started slowly building up years ago and although we could not have seen this when we moved in, many other preventable surprises can be detected with a home inspection.