Minor building alterations (internal) such as replacing or renovating a bathroom or kitchen may be carried out as exempt development without the need for development consent.
However, to be exempt, the work must comply with the specific exempt development standards in the State Codes SEPP, Part 2, Subdivision 26, Clause 2.51 and 2.52.
If the minor internal building alterations do not comply with the exempt development standards in Part 2, Subdivision 26 of the State Codes SEPP you may be able to undertake the proposed works as complying development subject to compliance with the specific provisions in the Codes SEPP–
Note: Under Part 4 - Internal alterations can be undertaken on any dwelling type (excluding heritage or draft heritage items) but only where a building was approved for strata subdivision or an occupation certificate was issued after 28 January 2000 (Clause 4.2).
Any proposal that does not comply with the development standards detailed in the exempt or complying provisions of the SEPP will require you to submit a Development Application.