: In our 1971 house anyone in the shower gets a cold awakening should someone else turn on the hot water elsewhere in the house (as in running a load of wash or running the dishwasher).

: Is there anything we can do to alleviate this problem? I've heard of devices for it, but wonder if anything is available for retrofit in other than new houses.

Colene,
Replacing the the shower faucet with a new "pressure balanced" one is the best way to go. The home centers are still selling the "non-code" shower faucets, but your plumber should be able to find you an "up to code" pressure balanced faucet. Terry