There was this case:
http://www.propertyobserver.com.au/find ... build.html
But that's only when the owner actually caught the builder doing the foundations\slab wrong, told them not to do so, they ignored him and went ahead with it. He used that against them in court and won. But most people don't have any idea how and when their slabs are built. And that could actually be one of the biggest reasons for all slab issues. When nobody is watching, they could do whatever they want, cut any corners they want to save them money and time and keep the profits. Otherwise, how can you explain that there could be 5 houses on one street (so clay type is the same for all) but only 1 out of 5 develops serious slab heave issues.
This is the actual case - http://www.austlii.edu.au/cgi-bin/sinod ... 20metricon
I am aware of another family that have been offered to buy back their homes from their builders. However in the above case, I believe that Metricon may have excercised their right to appeal the court decision.