Said It Here

What to do with old water pipes after removing a fixture?

Leaving inactive water lines open creates serious risks of accidental leaks, child tampering, and stagnation issues like dead legs. You need to properly secure and cap off these leftover secondary pipes using appropriate fittings or soldering to prevent future damage.

What the numbers show

Counted from the threads quoted below. How we count

  • This comes up 27.1× more often in r/HomeImprovement than across the site as a whole.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    leaving the bidet installed and making use of it
  2. 2
    leaving the pipe as-is in case someone wants to set up a bidet again
  3. 3
    tracing the pipe back and removing it lower down
  4. 4
    leaving the pipes capped and unused
  5. 5
    considering installing a small basin on the top floor to regularly flush water through

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/HomeImprovement3 people · September 2026

“I would definitely cap it. I would use a bidet to do so but if you want most big box stores will have stuff to cap and seal it.”source ↗

Mental-Huckleberry54 · r/HomeImprovement · 3 upvotes

“Absolutely cap off the pipe. You can do it with a sharkbite or solder.”source ↗

FearlessTomatillo911 · r/HomeImprovement · 1 upvotes

“when i remove the bidet, should i be doing anything with that second water pipe? though it will be off, it feels risky just leaving it them there, like if my toddlers accidentally twist either”source ↗

OddApplication2019 · r/HomeImprovement
r/Plumbing1 person · September 2026

“Am I correct that this has in effect left a 4m dead leg of pipework from the two branches that come off the middle floor, and also a nearer 10m dead leg of pipe from the ground floor branch that is meant to supply untreated water”source ↗

“Can I safely just leave things as they are for now after swapping the hard and soft and getting the toilet sorted?”source ↗

“Or is there something we need to be doing proactively to sort it?”source ↗

Primary_Ad45 · r/Plumbing · 2 upvotes

Where this came up

People with this problem also raised