"tim1198" wrote in message
ups.com...
Sounds like your plumber did not put air dampeners into your pipes,
which are risers teed of your line so that air can absorb the
vibrations and knocks.

Besides being annoying, it's probably not a huge deal. Except that if
he missed putting in these risers, what else did he miss? If you can
access the back of the plumbing through a closet or something
convenient, you can look at it and fix it.

good luck,
tim1198


Thanks to all, but to reiterate: it's not the knock that occurs when the
water is turned off. It's creaking that occurs when hot water heats up the
pipes.

Sounds like it's just something I'll have to accept.