Hello,

My house was built in 1963, in the Maryland suburbs of DC. It is a "rambler" with a walkout basement, which is partially finished. The unfinished portion is below (front) grade, and has the laundry room, a half bath, and storage. All of the piping is exposed so I have a decent idea of what is going on back there.

However, there is one pipe, the purpose of which I cannot determine. It is a copper pipe, about 2" in diameter. One end connects to the drain pipe for the slop sink in the laundry room. From there, it goes up the wall about three feet, makes a right turn, continues horizontal along the wall for about 10-12 feet, turns away from the wall, then back down where it connects to a pipe that drains an upstairs shower. On both ends, the drain pipes it connects to go down into the slab foundation. There are no other connections to this mystery pipe.

Does this pipe actually have a purpose? If I could take it out and just cap the joints where it connects now, would anything be impacted? Unfortunately, it runs through the half bath, which I am planning to finish (has shower rough-in already) myself, so if I could remove it, I'd gain a few inches for the shower stall.

I'm at work right now, but can take and post pictures/video tonight or tomorrow if needed.

Thanks.