General informationThis is not planning advice. Every planning application in NSW is lodged through the NSW Planning Portal, and your council or a registered certifier can tell you which pathways your lot can use.
The three routes side by side
The short version: the two complying development routes are faster and more rigid, because a proposal either meets every standard or it does not; a development application is slower and weighs the proposal on its merits against the council’s controls. The table sets out what the official pages say about each.
| Question | CDC under the Low Rise Housing Diversity Code | CDC with a pattern book design | Development application |
|---|---|---|---|
| Who decides | The council or a registered certifier. | The council or a private certifier. | The consent authority, usually the local council. |
| Measured against | Every development standard in the code, and the design guide’s criteria. | All the standards and specifications in the pattern, on an eligible site. | The council’s local environmental plan and development control plan, state policies, and in some areas the Low and Mid-Rise standards below. |
| How fast, as the department puts it | Approval can be issued within 20 days if the proposal complies. | Approvals can be issued in as little as 10 days. | The pages read for this guide give no standard figure. |
| Before building starts | Appoint a principal certifier; the certificate already includes construction approval. | The same: the department says construction can start once the certificate is approved, with a principal certifier appointed first. | Get a construction certificate and appoint a principal certifier. |
| Neighbours | In metropolitan areas, two notices, before approval and before work. | The same two notices in metropolitan areas. | Exhibition depends on the statewide plan; see Telling the neighbours. |
Inside a development application: the Low and Mid-Rise standards
Since 28 February 2025, a development application for a dual occupancy in a low and mid-rise housing area, in the R1, R2, R3 and R4 zones where it is permitted, is assessed against a set of state standards. As at October 2026 the department lists them as:
| Standard | As at October 2026 |
|---|---|
| Lot size | Minimum 450 m² |
| Lot width | Minimum 12 m |
| Floor space ratio | Maximum 0.65:1 |
| Height of building | Maximum 9.5 m |
| Car parking | 1 space per dwelling |
These are non-discretionary standards, also called non-refusal standards. The department explains that if a proposal complies with one, the council cannot refuse the application because it does not meet the equivalent standard in the local environmental plan or development control plan. They apply where they are more generous than the local controls, and every other control continues to apply as normal.
The low and mid-rise housing areas cover residential zones that lie within an 800-metre walk of nominated town centres and stations in Greater Sydney, the Central Coast, the Lower Hunter and Newcastle, and the Illawarra-Shoalhaven. The policy does not apply to land affected by certain hazards and constraints, which the department lists as including bushfire prone land, certain flood prone land, land near dangerous goods pipelines, land with high aircraft noise, land in a Transport Oriented Development area, land that is or contains a heritage item, and the Hawkesbury, Blue Mountains and Wollondilly local government areas.
After the approval: two timelines, side by side
The two families of approval end in the same place, an occupation certificate, but they get there in a different order.
After a development application
- Construction certificate. From the council or an accredited certifier, with detailed building plans and specifications. The consent’s conditions may first ask for extra reports, refundable bonds or development contributions.
- Principal certifier. Appointed by the person with the benefit of the consent, which the department explains means the owner, not the builder.
- Notice before work. The department’s DA guide says to give the council and the principal certifier two days’ notice before work starts, and to finish anything the consent lists for before work begins.
- Inspections. The guide says these generally include piers, slab, frame, stormwater, wet areas and a final inspection.
- Occupation certificate. Issued by the principal certifier once the final inspections are done and the requirements are met.
After a complying development certificate
- No second approval. The certificate already combines planning and construction approval.
- Principal certifier. Must be appointed before building work starts when the work needs a complying development certificate.
- Notice to neighbours. Neighbours within 20 metres must be told in writing before work starts: at least 7 days ahead in metropolitan areas, 2 days in rural and regional areas and residential release areas.
- Inspections. The principal certifier carries out the mandatory inspections during construction.
- Occupation certificate. Issued after the final inspections if all requirements are satisfied.
On either route, BASIX follows the project to the end: before the occupation certificate can be issued, the certifying authority has to issue a BASIX completion receipt confirming the homes were built as the certificate committed. The department’s older DA guide uses the earlier name for the principal certifier, the Principal Certifying Authority or PCA.
When the complying door is closed
If the lot is excluded, or the design misses a standard, the duplex goes by development application. The department says that adds on average more than 60 days for proposals that vary only slightly from the standards, and it has proposed a variations pathway to change that, set out on the code page.
A pattern book design can still be lodged as a development application on a site that is not eligible for complying development. The department says it then gets a full merit assessment by the council against all local requirements, and the design must still follow the pattern’s terms and conditions of use.
Finding a certifier
A construction certificate can come from the council or an accredited certifier. For a complying development certificate, the Planning Portal points to the Building Certifiers Public Register to search for a registered certifier.