How to tell which plumbing rough-in pipe is which
Unlabeled stub-out pipes leave homeowners guessing which drain corresponds to a toilet, shower, sink, or cleanout. Without clear markings, it is difficult to plan a basement bathroom layout or confirm if existing plumbing already serves a purpose before hiring a professional.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Asking online forum members to identify the pipes from photos
- 2Guessing based on pipe size
- 3Posting photos to online plumbing forums to ask experts for identification
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“About to start finishing my basement and I’m curious for the bathroom what’s what for my plumbing rough in?”source ↗
“My condo corporation has hired a plumber to install a cleanout under our kitchen sink tomorrow. But I'm looking right now and I'm wondering if we already have a cleanout...?”source ↗
“I took a photo under my kitchen sink. Can anyone tell me what the red arrow is pointing to?”source ↗
Where this came up
People with this problem also raised
- 2How to check a DIY plumbing layout before gluing
- 19How to identify unknown plumbing parts in a building
- 9How to find where an unmapped drainage pipe discharges
- 4How to tell if crusty residue on a basement pipe is a sewage leak
- 4Home inspection found plumbing issues but seller says it's fine
- 11What is this random dripping exterior pipe on my house?