When you're ready to start building, one of the most important early steps is understanding how your project will be approved.
In NSW, most new homes and duplexes are approved under one of two pathways: a Development Application (DA) through your local council, or a Complying Development Certificate (CDC) through a private certifier.
Both lead to the same outcome - a legally approved home - but they differ in speed, flexibility, cost, and complexity. Understanding these differences can help you set realistic expectations and avoid unnecessary delays.
To unpack how the two pathways work in practice, we spoke with Andrew Baker, Managing Director of Baker Built, a Central Coast custom builder experienced in guiding clients through both DA and CDC processes.
What is a Development Application (DA)?
A DA is the traditional approval route handled by your local council, with . It's designed for projects that don't neatly fit within the prescriptive rules for CDC. Council planners assess your proposal on merit, considering local planning controls such as zoning, setbacks, height limits, and design impacts.
Andrew says that for many homeowners, the DA process can take far longer than expected. "In my experience working with clients, the timeframe from the initial meeting through to contract signing is often around 12 months," he explains. "This extended duration is generally influenced by several recurring factors within both the DA and CDC processes."
The reasons are familiar to most builders: extended council assessment times, requests for additional information, and revisions to meet specific planning requirements. Even once approval is granted, it's common for clients to make design changes - whether due to budget constraints, shifting priorities, or builder feedback - which typically require a Section 4.55 amendment and add several more months to the process.
However, how long this process takes can vary between councils. We recently analysed real NSW data showing the wide range in average DA approval times across different areas. You can view the full breakdown in our article: How long NSW councils take to approve a DA.
Pros of DA:
- Allows greater design flexibility for unique or constrained sites.
- Can accommodate heritage, flood, or bushfire overlays.
- Provides an avenue for neighbour consultation or negotiated outcomes.
Cons of DA:
- Usually slower - approvals can take several months.
- Requires more documentation and professional reports.
- Subject to council interpretation and possible design revisions.
What is a Complying Development Certificate (CDC)?
A CDC is a streamlined, rules-based approval process available when your design fully complies with state planning standards.
Instead of a subjective merit assessment, a certifier checks whether your plans satisfy the fixed requirements in the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008.
To qualify for CDC, your project must meet every applicable standard in the Codes SEPP. Common requirements include:
- Zoning: Your land must permit the type of development proposed (e.g. detached house, dual occupancy).
- Lot size & frontage: The block must meet minimum dimensions specified in the Codes SEPP.
- Setbacks & height: Your design must comply with all setback distances and maximum building heights.
- Environmental constraints: CDC is unavailable on sites with certain overlays - for example bushfire, flood-prone, heritage, or environmentally sensitive land.
- Utilities & services: The property must have adequate sewer, stormwater, and access arrangements.
- Energy efficiency: BASIX and other sustainability requirements still apply.
If your design breaches even one of these criteria, you'll need to apply via DA instead.
Andrew says the CDC pathway "can, in many cases, offer a faster and more straightforward approval process than a DA, particularly where the proposed works fully comply with planning controls and building standards." However, he notes that similar challenges can still arise once pricing is received. "Despite the potential time savings, the same budgetary and design challenges tend to emerge. Design modifications are often required to align with the client's financial position. These changes can necessitate re-certification or amended documentation, which offsets the initial speed advantage of the CDC process."
Pros of CDC:
- Faster - typically approved within 20 days once documentation is complete.
- Lower overall costs (fewer consultants, reports, and revisions).
- Certainty in outcomes - if the design complies, it must be approved.
- Can use private certifiers, avoiding council backlogs.
Cons of CDC:
- Less flexibility - your design must meet every rule exactly.
- Not available for sites with heritage, flood, bushfire or environmental constraints.
- Limited opportunity for custom design or variations.
Public consultation: DA vs CDC
One of the biggest procedural differences between DA and CDC is community consultation.
A DA is lodged with your local council and must be publicly notified, allowing neighbours to review the proposal and submit feedback or objections. In some cases, this process can trigger design changes or extend the approval timeframe.
By contrast, a CDC is an as-of-right approval - meaning that if your design meets the state's standards, it can be certified without the need for neighbour consultation.
For homeowners, this often feels like a major advantage: less red tape, fewer delays, and no subjective objections from neighbours.
For neighbours, it can be a drawback - as they may have limited awareness of what's being built next door until construction begins.
Faster approvals with 'off-the-shelf' designs
One of the fastest ways to simplify approvals is to start with a design that's already known to comply.
Many volume builders have extensive catalogues of off-the-shelf plans that have been refined over time to meet CDC rules. Because these designs are tried and tested, they can often progress through certification with minimal changes - saving weeks of redesign and review.
If you're after a more sustainable approach, the Australian Government's Your Home initiative offers free, energy-efficient house designs developed by government architects. These climate-appropriate plans are available for a range of block types and can often meet CDC standards with the right site and orientation.
In NSW, the concept of pre-approved design has now extended into higher-density housing through the Pattern Book Development Code (2025). This new framework provides an even faster CDC pathway for dual occupancies, terraces, and manor houses built using pattern-book designs - pre-vetted templates that comply with strict parameters.
Pattern-book projects can be approved in as little as 10 days, with neighbours notified seven days before the decision. It's a sign of where housing approvals are heading: clearer rules, faster decisions, and a focus on well-designed, repeatable solutions.
Final thoughts
Both DA and CDC approvals can lead to a successful project - the difference lies in how closely your design fits within NSW's planning rules.
A DA gives flexibility and room for unique design solutions but comes with longer timeframes. CDC rewards compliance and precision but leaves less scope for variation.
Andrew says that while the CDC route can simplify approvals, "both DA and CDC projects are susceptible to delays caused by post-approval amendments and cost-driven redesigns." The most common reasons, he adds, are "council processing times, Section 4.55 amendments, budget adjustments, and limited flexibility with certifiers when altering approved plans."
Understanding these factors early - and finalising your design before submission - is key to avoiding unnecessary setbacks. By planning ahead and working with experienced professionals, you can navigate either pathway confidently and keep your build moving forward.