Hi Ladybird,

Expanding pipes causing noise is BS. You certainly have the right to live in a home with no banging pipes. I have come across many banging pipes during my carrier and there is simply too many causes to point to one thing. Reasons start with bad plumbing right through to cheap imported fittings.

Either way, you need to document this fault and submit a complaint with the builder (whoever your contract is with) and request for this to be fixed. If they refuse you can report this to the PGDB requesting an investigation. You may also engage a property / council inspector to provide a report which I assume will cost you a fee. I would try to get images of the plumbing done as this may indicate what the problem is right away.

Good luck with this.