GP obviously meant PEX, which is another plastic. (For people not familiar with modern plumbing: PEX is used for supply; PVC is used for drainage to the sewer.)
Maybe that’s what they meant, but PVC is also used for water distribution, cold water supply, and sprinkler piping (obviously all cold water but still pressurized supply applications), so it’s not at all clear that when they said PVC they meant PEX. CPVC is rated for domestic hot water supply, so they could have meant that as well. I’d say PEX was an underdog rather than the obvious alternative meaning.
