Ian Stirling wrote:
Grumps wrote:
Hi All

I read an article saying that copper will resist corrosion if laid
in a portland based concrete or mortar. Could someone explain why,
and what is the alternative to portland that WOULD corrode copper?
(Sorry, my knowledge of chemistry never was a strong point).

Err, it won't really resist.
In fact, it should never, ever be laid bare into concrete, and should
always be covered by something, be it the appropriate tape, or
whatever.

Hessian sleeve with a polyurothane lining. That's what our plumber has used.
I assume that's ok as he's been doing it (hopefully correctly) for 25 years.