Project sector
Secondary Dwellings
A secondary dwelling, or granny flat, is a self-contained dwelling on the same lot as the principal home. Where the lot and the design meet the standards, it can usually be approved as complying development.
Overview
Secondary dwellings are enabled by the State Environmental Planning Policy (Housing) 2021, which sets where they are permitted and the standards they must meet, including a maximum internal floor area, commonly 60 square metres. Where the lot is eligible and the proposal complies, a Complying Development Certificate is available; where it does not, a development application applies.
A secondary dwelling is a Class 1a building, so the usual certification chain follows: approval, construction, critical stage inspections and an Occupation Certificate. A secondary dwelling shares the lot with the principal dwelling and generally cannot be subdivided onto its own title.
Typical pathway
- 01
Eligibility
We confirm the lot meets the minimum size and the proposal fits the secondary-dwelling standards.
- 02
Approval
A CDC where the standards are met, otherwise a DA and Construction Certificate.
- 03
Construction
Critical stage inspections proceed through the build.
- 04
Completion
Occupation Certificate for the secondary dwelling.
What shapes the assessment
Floor area
The internal floor area is capped, commonly at 60 square metres, separate from the principal dwelling.
Lot size & one per lot
A minimum lot size applies, and generally only one secondary dwelling is permitted on a lot.
Not separately saleable
It shares the lot with the principal dwelling and generally cannot be subdivided onto its own title.
BASIX & open space
A BASIX certificate is required, and private open space provisions apply. Off-street parking is not a complying development requirement for a secondary dwelling.
Ready to get started?
Adding a granny flat?
Send the lot and concept details. We will confirm whether the secondary dwelling can be approved as complying development.
We respond to enquiries within one business day.