Most forms of development in NSW requires some form of consent - usually from the local Council, although increasingly in many instances it can also be obtained from an accredited private certifier.
It is not uncommon, however, for persons to perform development without first obtaining the necessary consent. This is particularly the case for smaller developments. Many persons are often unaware that the change of use of a building or unit may also require consent.
There are a range of powers that Councils have under the Environmental Planning and Assessment Act 1979 to address unauthorised building work. Councils often become aware of unauthorised building work due to complaints from local residents or they may perform random inspections/audits of properties in their area.
Orders that Councils may issue for unauthorised building works are set out in Schedule 5 of the Environmental Planning and Assessment Act 1979. They cover a range of categories including stop use orders, stop works orders, demolish works orders and remove advertising orders.
The Act and Regulations specify procedures that must be followed by Councils prior to and in issuing an order. Often a "notice of intention" of a proposed order must first be issued, giving the owner of the property the opportunity to make representations prior to the order being issued. There are also appeal rights against the issue of many orders in the Land and Environment Court.
Councils may not always act in a completely legalistic way and Council officers may in many cases discuss a potential issue verbally with the affected party first before issuing an order.
The state government also has a compliance role with respect to "state significant" developments.
Often, owners of a property may seek to resolve unauthorised building works by seeking retrospective approval for them. The practice of this may vary according to the policies/procedures of each individual Council. A "Building Information Certificate" can be issued by the Council which prevents it from issuing certain further orders with respect to the building for the next seven years. A Council could also request a Development Application or Modification Application to be lodged. Potential ways forward may be outlined verbally or in writing by Council officers.
For further information on orders and unauthorised building work, check out my book.