This issue I am having is little different than " How do I fix "water hammer" problem asked a few years ago.
1 The problem I am having started a month ago after living in this house for 10 years with no problem.
2 All faucets during shut off create a thud sound.
3 The sound comes from a single location somewhere upstairs either in the wall or attic
4 If I turn off the faucets slowly, I do not get it.
5 Both hot and cold faucets create the sound
6 My incoming city water pressure is 75 psi
7 I tried to shut off all water, drain pipes and restart but it did not work
8 No noise for Toilets or Washing Machines or showers surprisingly. Only all faucets.
9 Putting hammer arresters on every faucet is impractical, right?
Need help. Thanks