Australia has a national level building code. Below is a summary of the relevant codes and bodies. There are a number of aspects to the code which provide a challenge to tiny house builders due to size restrictions.
The Australian Building Code Board (ABCB)
National Construction Code (NCC)
The National Construction Code (NCC) provides the minimum necessary requirements for safety and health; amenity and accessibility, and sustainability in the design, construction, performance and livability of new buildings (and new building work in existing buildings) throughout Australia. It is a uniform set of technical provisions for building work and plumbing and drainage installations throughout Australia whilst allowing for variations in climate and geological or geographic conditions.
The NCC is an initiative of the Council of Australian Governments (COAG) developed to incorporate all on-site construction requirements into a single code. The NCC is comprised of the Building Code of Australia (BCA), Volume One and Two; and the Plumbing Code of Australia (PCA), Volume Three.