Requirements for Secondary Residences in the ACT

April 1, 2022

Granny Flats are known as ‘secondary residences’ in the ACT and are required to comply with regulations that are slightly different to those in NSW, hence why it is so important to refer to your local and state laws in the planning stages. Prior to 2013, the use of secondary residences was restricted for use solely by older family members of relatives. These days however they can be used for a wide variety of purposes.

The ACT requires a Development Application (DA) to be approved prior to the commencement of any building. In this process, a floor plan must be submitted to your local council showing the Granny Flat is compliant with the Australian Standard AS 4299 Adaptable Housing (Class C). This standard is to ensure the residence is easily adaptable to cater to the needs of people with disabilities.


Other requirements that must be met for the construction of a secondary residence include:

  • Must be located in a residential zone
  • Situated on a property with a minimum size of 500m²
  • Minimum floorspace of 40m² and a maximum of 90m²
  • Must include a private open space for tenants and at least one off-street car parking space
  • Must have clear and unobstructed pedestrian access
  • Is compatible with the exterior building materials of pre-existing buildings in the neighbourhood
  • Only the property owner can own the Granny Flat, and there may only be one per property
  • Must not inhibit the privacy of adjoining residences
  • Must maintain setbacks of 1.5m from one side and 3m from the other, 3m from the rear and 6m from the front

Being a proudly Australian, family owned and operated business, the Cubitt’s team are committed to bringing your visions to life. This is why we created an entire range of Granny Flat designs specifically to meet the regulations in the ACT. Contact our friendly Cubitt’s Design Consultants to learn more about our 90m² Collection on 1300 721 150 or

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About Vince Zinghini

Vince is Cubitt's Director of Planning. With two decades experience in NSW and ACT Council planning and a team of people covering the specific areas in which Cubitt's build, its rare to find a planning scenario we haven't been able to tackle.