The best replacement for copper pipes is pvc.

The best alternatives to copper pipes are rated as following:
★★★★★  pvc
★★★  plastic pipes
★★★  pvc pipes
★★★  pex
★★  galvanized
★★  cpvc
★  galvanized pipes
★  flex pipes
  plastic plumbing
  pcv pipes
  cpvc pipes
  e-pipes

Your alternative for copper pipes is not listed? Suggest!
Speaking about copper pipes, one probably shouldn't forget about lead solder.

Other search terms related to copper pipes and their ratings are:
★★★★★ lead solder
You have in mind a companion for copper pipes and it is not yet here? Propose!



Google Trends

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copper pipes
pvc
plastic pipes