How to use this checklist
Work through the steps in order. Each one either confirms your duplex is viable or flags something to resolve before you spend on the next stage. The earlier a constraint surfaces, the cheaper it is to design around.
How to get a duplex approved in Sydney
- 1
Confirm zoning and permissibility
Check your zoning and whether dual occupancy is permitted, using the Section 10.7 planning certificate and the council LEP.
- 2
Check lot size and frontage
Confirm your lot area and frontage against the CDC benchmark (450m² / 12m) and your council's DA minimums.
- 3
Identify overlays
Check flood, bushfire (BAL), heritage, easements and significant trees. These often decide CDC vs DA.
- 4
Choose the approval pathway
Based on eligibility and design goals, decide between a CDC fast-track and a merit-assessed DA.
- 5
Set your subdivision strategy
Decide Torrens or strata early so the design and party wall support your title outcome.
- 6
Prepare the design and documentation
Develop the architectural design and coordinate consultants (surveyor, BASIX, stormwater, and any specialists the overlays require).
- 7
Lodge and respond
Lodge the application and respond promptly to any RFI (request for information) with revised plans.
Sydney Duplex Approval Checklist (PDF)
Frequently asked questions
Confirm zoning and lot feasibility. There's no point designing until you know a duplex is permissible and the numbers work, that's what the checklist starts with.
Authoritative sources: NSW Planning Portal, NSW Low Rise Housing Diversity Code.