DA vs CDC: Which Approval Path and What Engineering Is Needed?

What You Need to Know

In NSW, most construction projects need one of two approvals before work starts: a Development Application (DA) through council, or a Complying Development Certificate (CDC) through a private certifier. Both lead to the same outcome, a lawful building, but the process, timeline, and engineering requirements differ significantly.

A DA goes to the local council for assessment against the Local Environmental Plan (LEP) and Development Control Plan (DCP). It takes 40 to 90+ days and involves council planners exercising discretion over the proposal. A CDC is issued by a private certifier (or council) and takes 10 to 20 business days. It is only available if the development meets the strict criteria in the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008, commonly called the Codes SEPP.

The engineering scope is similar for both pathways. The difference is timing. A DA separates planning approval from construction approval (the subsequent Construction Certificate). A CDC combines them into a single step. This means all building services engineering documentation must be ready at CDC application stage, not later.

• DAs are assessed under Part 4 of the Environmental Planning and Assessment Act 1979 (NSW). Council planners assess the proposal against the LEP, DCP, and any relevant State Environmental Planning Policies. There is no guaranteed assessment timeline. (EP&A Act 1979, Part 4)
• CDCs are assessed under Part 4, Division 4.5 of the EP&A Act. The development must comply with the Codes SEPP. The certifier checks compliance against objective criteria with no discretion. If it meets the criteria, the CDC must be issued. (EP&A Act 1979, Division 4.5)
• CDC eligibility depends on the site and the proposed development. Heritage items, flood-prone land, bushfire-prone land (BAL-40 and BAL-FZ), environmentally sensitive areas, and developments exceeding height or floor space ratio limits in the Codes SEPP are excluded. (Codes SEPP 2008)
• A Construction Certificate (CC) is required after a DA is approved. The CC is where detailed engineering documentation is assessed for NCC compliance. Building services engineering reports (mechanical, electrical, hydraulic, fire protection) are typically required at CC stage. (EP&A Act 1979)
• A CDC replaces both the DA and the CC. All engineering documentation that would normally be submitted at CC stage must be included in the CDC application. The certifier assesses NCC compliance as part of the CDC process. (EP&A Act 1979, Codes SEPP 2008)
• Section J energy compliance is required for both pathways. Whether through DA+CC or CDC, the building must demonstrate compliance with NCC Section J via Deemed-to-Satisfy or JV3 before construction can begin. (NCC 2025 Section J)
• Some councils require engineering reports at DA stage, not just CC stage. This varies by council and by development type. Check the council's lodgement requirements before assuming engineering can wait until CC. (Local council DA lodgement guides)

For a straightforward project, say a new warehouse on a greenfield industrial lot, the CDC pathway is almost always faster. The site is unlikely to have heritage, flood, or bushfire constraints. The building form is simple. The Codes SEPP criteria are easy to meet. A private certifier can issue the CDC in 10 to 15 business days. Compare that to a council DA that might take three months with requests for additional information along the way.

The catch is that CDC requires all documentation up front. For building services engineering, this means mechanical design (HVAC layout, equipment schedules, Section J compliance), electrical design (lighting, power, switchboard schedules), hydraulic design (water supply, drainage, stormwater), and fire protection design (hydrants, sprinklers, detection) must all be complete before the CDC application is lodged. On a DA pathway, these reports can often wait until the Construction Certificate stage, which might be months after the DA is approved.

This timing difference affects your consultant engagement. On a CDC project, you need all engineering disciplines working in parallel from day one. On a DA project, you might engage the architect first, get DA approval, then bring in the engineers for CC documentation. The total engineering cost is similar, but the cash flow profile is different. CDC front-loads the consultant fees.

DA is the only option for projects that do not meet CDC eligibility criteria. A mixed-use development on a heritage-listed site cannot use the CDC pathway. A residential flat building that exceeds the height limits in the Codes SEPP must go through DA. A commercial project on flood-prone land needs a DA with a flood impact assessment. In these cases, there is no shortcut.

DA also provides flexibility that CDC does not. Council planners can exercise discretion and approve proposals that do not strictly comply with every numeric control in the DCP. A building that is 200mm over the height limit might be approved on merit through a DA. Under CDC, the same 200mm would be a fatal non-compliance and the application would be refused.

CDC application fees are lower than DA fees. A typical council DA lodgement fee for a commercial project ranges from $5,000 to $30,000+ depending on the estimated development cost. CDC fees through a private certifier are typically $3,000 to $15,000. The real saving is not in fees but in time. Every week of faster approval reduces holding costs on land, financing, and lost rental income.