You only need to apply to be an owner-builder if you are doing your own work instead of hiring someone who is already permitted to do the work. This is no different from the US practice of having licensed contractors/electricians carrying out (or signing off on) large projects.
You only need to apply to be an owner-builder if you are doing your own work instead of hiring someone who is already permitted to do the work.
That is precisely what we are discussing. The restrictions on doing work on your own house yourself.
And this applies to any work at at, not just work that requires licensing (plumbing, electrical etc.). Even if you're doing the overall work yourself as an owner builder, you still need to hire licensed professionals for those tasks.
In Victoria for example, you're not allowed to do any work on your own home if it exceeds a certain monetary value without first running through a Kafkaesque bureaucratic process to obtain a certificate.
This doesn't sound unreasonable until you realize that they don't care if you have any qualifications related to the work and don't even want to know what the work is. They simply want to confirm that you haven't done any other work (on your own property) in the last five years.
If you have, sorry, need to hire a registered builder. This prevents anyone from legally buying a home, renovating, and selling it, or even doing any significant work on your own property more than once in five years.
And if you want any other tradesperson to come to assist for anything while your doing it (installing a power point for example), then you need in person occupational health and safety training at a "registered training institute".
http://www.vba.vic.gov.au/consumers/owner-builders