In article , Tricky
Dicky wrote:
We had a gas leak in a pipe buried in plaster, I only detected it because
gas was coming out of a socket that the pipe ran close to. Turned out it
was a soldered joint that had given having lasted 33 years. The gas
engineer who sorted it told me that chemicals in the plaster react with
the lead/tin solder. I do believe running gas pipes in plaster is now
discouraged but if it cannot be avoided they should be sleeved.

same applies to copper water pipes.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle