PVC pipes making clicking noise. Normal?
We did a complete remodel of the home we bought a few years back. We now have PVC pipes running in the walls/attic. The problem I have is that when I run the sinks (hot water), flush a toilet or start the washing machine the pipes make a clicking noise (like a drip, drip, drip - but it's not leaking). DH says it's the pipes expanding, there's nothing we can do about it and it's not a big deal. It drives me crazy and people I talk to say it would drive them crazy as well. DH is a very laid back guy (which is usually wonderful)!
Is this normal? Let me add that the plumber was incompetent/duh in other areas - which makes me question his work. He ran the air-conditioner in the middle of construction (saw dust, vents taped up) because he was hot. He swore our German kitchen faucets were defective because he couldn't get hot water from them (hot and cold were reversed - DH solved this problem before plumber pulled them out to send back - which he was insisting needed to be done). Those are the two that stick out. Also, I know my contractor does not use him anymore.
Can this be "repaired"? Contractor came out once, cut wall open and attempted (lasted for about a week before clicking noise back).
Thanks in advance.