Public Plumbing Question

I happen to be visiting a number of public restrooms recently, restaurants, college buildings, airports etc. and I began to notice something that I hadn’t noticed before. On the drain pipes of most of the sinks it appears that they are being wrapped with some kind of tape or adhesive material. It almost looks like some kind on insulation, but I don’t see any reason why you would insulate drain pipes.

So what’s the deal? These bathrooms are indoors, in California, so there is no chance they are going to freeze. And how can they get at the traps if they are wrapped so tight? If someone loses their wedding ring down the drain it will take a lot of work to get at the trap to see if it’s there. Does anybody know why this is being done? There must be a logical reason…

Its primarily to reduce/eliminate condensation on the pipe, so that it doesn’t drip down onto the floor and cause false reports of leakage, and to keep the area more tidy/dry.


I also believe that it is an Americans with Disabilities Act requirement that sink drain pipes be insulated so that wheelchair users won’t risk injury. According to this site, “Exposed plumbing under barrier-free lavatories must be either insulated or located to eliminate any contact. Sharp edges must be avoided.”

Yep, it’s an ADA thing in the US. At a minimum, the hot water line and the drain must be insulated so someone who’s rolled up to the sink in a wheelchair doesn’t get burned by hot pipes.

I have seen some installations with PVC plastic drains where only the hot water line was insulated, on up to insulating everything, including the cold water line. A relatively recent development is pre-formed fabric or plastic insulation that slips over the plumbing and is secured with zip-ties, so getting at the pipes only requires snipping a few ties, rather than cutting off or unwinding pipe wrap.