This guide explains state-by-state granny flat rules, outlines how to get granny flat approval, and breaks down the two main approval pathways: Complying Development Certificate (CDC) granny flat and Development Application (DA) granny flat. You’ll also find practical tips to help achieve fast track granny flat approval where possible.
CDC vs DA (what every homeowner needs to know)
Understanding the difference between approval pathways is critical before you start designing or budgeting.
- CDC granny flat: A Complying Development Certificate is a fast-track approval option for designs that meet strict, predefined standards such as maximum size, setbacks, site area, and height. If your proposal complies fully, approval can often be issued quickly by a council or private certifier without public notification.
- DA granny flat: A Development Application is required when your design does not meet complying standards or when additional planning controls apply. A DA is assessed by the local council and may involve longer timeframes, public notification, and additional documentation.
Choosing the correct pathway early can significantly affect approval time and overall project cost.
State-By-State Rules (high-level — always check your local council first)
New South Wales (NSW)
In NSW, secondary dwellings can often be approved under the State Environmental Planning Policy (Housing). Many granny flats qualify for a CDC if the site and design meet set standards.
A key requirement is usually a minimum lot size of around 450 m², along with specific setback and floor area limits. If these controls are not met, you will need to lodge a DA granny flat with council.
Victoria (VIC)
Victoria has simplified approvals for small second homes. In most cases, a planning permit is not required for a granny flat up to 60 m², although a building permit is still mandatory.
Be aware that planning overlays such as heritage, flood, or native vegetation controls can still trigger additional permit requirements. Where no overlays apply, approvals are often much faster.
Queensland (QLD)
In Queensland, building approval is always required, while the need for a development application depends on local planning schemes.
Since September 2022, occupancy rules have changed, allowing secondary dwellings to be rented to non-family members in most areas. Early consultation with your local council is recommended to confirm permit requirements for granny flats and determine whether your project can follow a code-assessable pathway.
Western Australia (WA)
WA has updated its planning framework under the R-Codes to make ancillary dwellings easier to approve. If your design meets deemed-to-comply standards, planning approval may not be required.
While previous rules capped internal floor areas at around 70 m², recent reforms have relaxed several restrictions. Building permits remain mandatory, and all designs must comply with the R-Codes.
South Australia (SA)
South Australia has streamlined planning rules to support secondary dwellings and rental supply. Whether you need a development application or can follow a simpler approval process depends on zoning, overlays, and site conditions.
Because requirements can vary by suburb, it is essential to confirm local permit requirements for granny flats with your council before proceeding.
Tasmania (TAS)
In Tasmania, granny flats are often referred to as “small second dwellings,” typically capped at around 60 m² and commonly required to share services with the main dwelling.
Some councils allow a “No Permit Required” or simplified pathway, although building and plumbing approvals are still necessary. Always check with your local council for the most accurate information.
Australian Capital Territory (ACT)
The ACT has specific rules governing secondary residences. In most cases, a Development Application is required through the ACT Planning Authority, and public notification may apply.
Size limits and site requirements depend on zoning, so most homeowners should expect to follow a DA pathway unless their proposal clearly meets all secondary dwelling criteria.
Northern Territory (NT)
In the NT, granny flat approvals are governed by the NT Planning Scheme. Some projects may be exempt from planning approval if they meet scheme controls, but building approval is always required from a registered certifier.
If additional variations or constraints apply, a development permit will be necessary.
Step-by-Step Checklist to Get Granny Flat Approval
- Check your local planning rules: Start with your state planning portal, then confirm requirements with your local council.
- Measure your site: Confirm lot size, setbacks, easements, and overlays such as bushfire, flood, or heritage controls.
- Decide CDC or DA: If your design complies with deemed-to-comply standards, pursue a CDC granny flat; otherwise lodge a DA granny flat.
- Prepare documentation: Site plans, architectural drawings, engineering, energy compliance (such as BASIX in NSW), and owner consents.
- Engage a certifier or planner: Private certifiers can issue CDCs, while DAs are assessed by council planners.
- Obtain building approval: Secure the building permit or construction certificate before starting work.
- Final occupancy certification: Complete inspections and approvals before occupying or renting out the dwelling.
Tips to fast-track granny flat approval
- Design your granny flat to meet your state’s standard controls for size, setbacks, and height to improve eligibility for fast-track granny flat approval.
- Use a private certifier for CDC approvals, as this is often faster than a council-assessed DA.
- Request pre-lodgment advice if overlays or site constraints may apply, helping to avoid costly delays.
- Where required, retain shared services such as sewer, stormwater, and power connections to support compliant pathways.
Final note
Planning rules across Australia are evolving, with many states easing controls to support housing supply. While this is positive for homeowners, the requirements for granny flats still depend on your state, zoning, and individual site conditions.
Start by reviewing your state planning portal and speaking with your local council. Professional advice can also help determine whether your project qualifies for a CDC pathway or requires a DA.
By understanding the state-by-state rules and confirming local requirements early, you can move forward with confidence. If you want expert support, Master Granny Flats can guide you through approvals and help deliver your project efficiently.
