top of page



A compact secondary dwelling beside your main house, called a granny flat, provides several benefits to property owners. You can use it as additional accommodation for your distant relatives or to earn rental income and pay off your investment.

If you’re looking to start your granny flat project in the foreseeable future, you must know about the standard granny flat council requirements in NSW. Knowing these requisites will save you time, effort, and money because you won’t have to go through specific processes repeatedly.


The State Environmental Planning Policy (Affordable Rental Housing) (AHSEPP), which was introduced in July 2009, permits the building of granny flats even without council approval. The NSW Government acknowledges a granny flat as an actual home, an accessory apartment, or an accessory dwelling unit.

Because council approval is not required, the entire planning and construction process can now be completed in about 12 weeks. Your property and design plans must still adhere to specific NSW construction requirements.


  • You cannot exceed the maximum internal space of 60 square metres.

  • You ought to have a minimum lot area of 450 square metres.

  • You can only build a maximum of one granny flat per lot.

  • Your granny flat must maintain a height of 8.5 metres maximum.

  • You must have a courtyard space of 24 square metres for your granny flat.

  • You must maintain a 12-metre width at the building line of your current main house. You may want to consider attaching the granny flat on your main house if your property doesn’t meet this requirement.

  • You must keep a setback of three metres from the rear of the main house and 0.9 metre from its side boundaries.

  • You must keep a distance of three metres from any existing trees that have a height of more than six metres.

  • Must be 1.8m distance from all other structures


Is it legal to build a granny flat instead of a house on empty land?

No, you cannot build granny flats on unoccupied lots according to the current guidelines of the AHSEPP. You can only build them on a property with an existing building or house.

Can you build a two-storey granny flat on your property?

You may build a two-storey granny flat on your property according to AHSEPP. However, it must adhere to the rear and front setback requirements of the NSW policy.

Can you build a granny flat larger than 60 S/M?

In NSW, the maximum secondary dwelling size is 60 square metres. However, it is possible to build a granny flat with a floor space that is larger than this.


For this you will need to submit a full Development Application (DA). As opposed to the common Complying Development Certificate (CDC)


Up to 100 square metres could be an option if;

  • Your block of land is big enough.

  • Your local Council is feeling indulgent!

  • However at a larger size such as this it will be difficult to class it as a “secondary dwelling” or Granny flat.




Survey, Property Searches & Reports

  • Site Survey, Property Searches and Compliance Report

  • Initial Survey and Approval Report


Does the property slope towards the rear boundary? Is the property served by a drainage easement? 

  • Dispersion Pit is needed for Drainage - Additional Engineer Design

Do any significant trees need to be removed or is the Granny Flat to be built within 3 metres of a tree trunk?

  • DA Approval must be sought from your local council - additional approval

  • Detail Survey by a Registered Surveyor needed - AHD survey

Does the Sewer Mains run through the middle of the rear yard? Can the structure be built 600mm or more from the Sewer Mains pipe

  • No - Concrete Encasement is needed - Additional Engineers Design

  • Yes - Longer Piers must be designed by a Civil Engineer - Additional Engineers Design


Certifier (or Council) Approval Granted

  • Total Building Approval incl. Occupation Certificate

bottom of page