Design and Building Practitioners Act 2021: What Apartment Developers Must Know
Author: Franz Phan, Registered Design Practitioner (Class 2 Medium-Rise), giantA Pty Ltd Published: July 2026 Reading time: 12 minutes
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Introduction: Why the DBP Act Changed Everything for Apartment Development
If you are developing a residential apartment building in New South Wales today, the regulatory landscape you navigate bears almost no resemblance to the one that existed before 1 July 2021. The Design and Building Practitioners Act 2020 (NSW) — commonly called the DBP Act — together with the Design and Building Practitioners Regulation 2021, introduced the most significant overhaul of building compliance in the state's history. For apartment developers, the changes are not bureaucratic trivia. They dictate who can design your building, how those designs must be documented, what declarations must be lodged before construction begins, and what penalties apply if things go wrong.
The reforms arose from a crisis of confidence. High-profile defects in apartment buildings across Sydney — combustible cladding, waterproofing failures, structural inadequacies — eroded public trust and prompted the NSW Government to act. The result was a three-pillar framework: the Residential Apartment Buildings (Compliance and Enforcement Powers) Act 2020 (RAB Act), which granted sweeping enforcement powers to the Building Commissioner; the DBP Act, which mandates registration and compliance declarations for practitioners; and the Building Legislation Amendment (Design and Building Practitioners) Act 2023, which expanded coverage to Class 3 and Class 9c buildings.
For developers, understanding these obligations is not optional. Non-compliance can delay occupation certificates, expose you to disciplinary action, and render your building uninsurable. This guide explains what the DBP Act means for your next apartment project, who needs to be on your project team, and how to keep your development on the right side of the law.
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What Is the DBP Act and Why Was It Introduced?
The DBP Act commenced on 1 July 2021 and established a mandatory registration scheme for design practitioners, building practitioners, and principal design practitioners working on regulated buildings. Its central purpose is to ensure that designs and building work comply with the Building Code of Australia (BCA), which sits within the National Construction Code (NCC). Under the Act, practitioners must prepare regulated designs, make design compliance declarations, and lodge these documents on the NSW Planning Portal before building work begins.
The Act imposes a statutory duty of care on practitioners. A registered design practitioner who signs a compliance declaration is personally accountable for ensuring that the design, if followed, will result in building work that meets the BCA. This accountability cannot be delegated to a junior team member or buried in a consultancy agreement. The practitioner who declares is the practitioner who carries the legal risk.
For developers, this shifts the risk landscape. Pre-2021, a developer could engage a design team, receive drawings, and proceed to construction with limited visibility into whether each discipline had formally certified their work. Today, every regulated design must be declared and lodged before the first nail is driven. A certifier cannot issue a construction certificate or complying development certificate without these documents. The consequence is that any gaps in your design team's registration status, or any delays in preparing compliant documentation, become project-critical path items.
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Which Building Classes Are Regulated?
The DBP Act currently applies to Class 2, certain Class 3, and Class 9c buildings. Understanding where your project falls is the first step in determining your obligations.
| Building Class | Description | DBP Act Status | Examples |
|---|---|---|---|
| Class 2 | Multi-unit residential buildings where occupants live above or below each other | Fully regulated since 1 July 2021 | Apartment buildings, residential flat buildings, mixed-use with residential component |
| Class 3 | Residential accommodation for unrelated persons (hotels, motels, boarding houses) | Partially regulated from 3 July 2023 for new buildings; existing buildings from 1 July 2028 | Hotels (if not strata), motels, backpacker hostels |
| Class 9c | Residential care buildings where ≥10% of residents need daily assistance | Regulated from 3 July 2023 for new buildings; existing from 1 July 2028 | Aged care facilities |
| Class 1 | Detached houses, townhouses, terrace houses | Not regulated under DBP Act | Single dwellings, dual occupancies (Class 1b) |
Class 2 remains the most heavily regulated category and the one most relevant to apartment developers. Notably, the Act applies not just to standalone Class 2 buildings but also to mixed-use developments where a Class 2 component exists — for example, apartments above a commercial podium or car park. In these cases, regulated designs are required for all parts of the building, not just the residential component.
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The Three Key Obligations: Design, Declare, and Lodge
The DBP Act creates a linear compliance workflow that runs from design conception through to construction commencement. Developers who understand this workflow can plan their project timelines accordingly and avoid the costly delays that occur when compliance documentation is treated as an afterthought.
1. Prepare Regulated Designs
A regulated design is not merely a set of architectural drawings. It is a formal document — drawing, schedule, specification, or report — that addresses a building element or performance solution for a regulated building class. Building elements include structural components, fire protection systems, waterproofing, and mechanical, electrical, and plumbing services. Performance solutions are alternative compliance pathways that satisfy the BCA's performance requirements through methods other than deemed-to-satisfy provisions.
Each regulated design must be prepared by a practitioner registered in the appropriate class. For a medium-rise apartment building, this typically means engaging a design practitioner — building design (medium-rise), a design practitioner — structural engineering, a design practitioner — hydraulic engineering, a design practitioner — mechanical engineering, and a professional engineer — fire safety. The principal design practitioner coordinates these inputs and ensures that the designs are integrated and consistent.
2. Make Design Compliance Declarations
Before any building work begins, each registered design practitioner must make a design compliance declaration. This declaration confirms that the design complies with the BCA and, where relevant, takes into account other regulated designs that interface with it. The declaration is not a generic statement of competence. It is a statutory declaration that carries personal liability.
The standard compliance declaration forms were updated on 16 January 2023 and are available through the NSW Planning Portal. Practitioners must use the current versions; outdated forms will be rejected. The declaration must be accompanied by a standard title block positioned in the top left-hand corner of the design document. The title block contains metadata that the Planning Portal extracts automatically, including the practitioner's registration number, the development application number, and the version of the design.
3. Lodge on the NSW Planning Portal
The building practitioner — typically the builder or project manager — is responsible for lodging regulated designs and compliance declarations on the NSW Planning Portal before construction commences. The portal creates a permanent, auditable record of every design version, declaration, and variation. This record is accessible to certifiers, the Building Commissioner, and owners corporations.
Critically, a certifier cannot issue a construction certificate or complying development certificate without confirmed lodgement of the required regulated designs and declarations. This means that any delay in your design team's ability to produce compliant documentation flows directly into your construction start date.
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Who Needs to Register? A Developer's Checklist
Developers are not themselves required to register under the DBP Act, but they are responsible for ensuring that every practitioner on their project team holds current, appropriate registration. The following table summarises the key registration classes relevant to apartment development.
| Registration Class | Authorised Work | Typical Role on Project |
|---|---|---|
| Design Practitioner — Building Design (Medium-Rise) | Design of residential apartment buildings up to 3 storeys above basement | Lead design consultant; architectural and spatial coordination |
| Design Practitioner — Structural Engineering | Structural components, shoring, underpinning | Structural engineer |
| Design Practitioner — Hydraulic Engineering | Plumbing, drainage, stormwater | Hydraulic consultant |
| Design Practitioner — Mechanical Engineering | HVAC, ventilation systems | Mechanical engineer |
| Professional Engineer — Fire Safety | Fire safety engineering solutions | Fire safety engineer |
| Principal Design Practitioner | Coordination and lodgement of designs by other practitioners | Design manager; sometimes the lead architect |
| Building Practitioner | Lodgement of designs and declarations; oversight of construction | Builder; project manager |
A common misconception among developers is that an architect automatically holds the necessary registration to design a Class 2 building. This is not always the case. Architecture is a regulated profession under the Architects Act 2003 (NSW), but architectural registration does not confer DBP Act registration. A practitioner must hold both: registration as an architect (or other building design qualification) and separate registration under the DBP Act in the relevant class. Before engaging any design consultant for a Class 2 project, verify their DBP Act registration status on the NSW Planning Portal practitioner register.
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Developer Responsibilities Under the RAB Act
While the DBP Act governs practitioners, the RAB Act imposes direct obligations on developers. Under the RAB Act, developers must give notice to the Building Commissioner of the date they intend to apply for an occupation certificate. They may also be required to pay the building work levy, which funds the regulator's compliance and enforcement activities.
The RAB Act grants the Building Commissioner extraordinary powers, including the ability to issue building work rectification orders, stop-work orders, and prohibition orders. The Commissioner can also require developers to produce documents and attend interviews. These powers are not theoretical. Since 2020, the Commissioner has issued numerous rectification orders and publicly named developers who have failed to comply.
For developers, the practical implication is that compliance cannot be outsourced to consultants and forgotten. You need a compliance framework that tracks registration status, lodgement dates, variation records, and rectification obligations. At giantA, we maintain a project compliance dashboard for every Class 2 development we design, giving our developer clients real-time visibility into their regulatory position.
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Real Project Examples: How Compliance Works in Practice
Example 1: 12-Unit Apartment Building, Parramatta — Design to Approval in 14 Weeks
In late 2023, a private developer engaged giantA to design a 12-unit, three-storey apartment building in Parramatta under a complying development certificate (CDC) pathway. The site was zoned R3 Medium Density Residential and had no heritage constraints. Our team — led by a Registered Design Practitioner (Building Design, Medium-Rise) — prepared regulated designs for architectural layout, structural engineering, and fire safety. Each design was declared by the relevant practitioner and lodged on the NSW Planning Portal within one day of being issued for construction. The CDC was issued three weeks after lodgement, and construction commenced on schedule. The total design-to-approval timeline was 14 weeks. Key lesson: early coordination between the design practitioner and the certifier prevented the back-and-forth revisions that typically add four to six weeks to a project.
Example 2: Mixed-Use Building, Liverpool — DA Pathway with Performance Solutions
A 24-unit apartment building with ground-floor retail in Liverpool presented greater complexity. The site had a 6-metre fall, requiring a performance solution for fire egress and a retaining wall that interfaced with the neighbouring property. Our structural engineer prepared a regulated design for the shoring and underpinning, while our fire safety engineer developed a performance solution for the extended travel distances. Because these designs depended on each other, the principal design practitioner managed a staged lodgement process: structural designs lodged first, followed by fire safety once the structural parameters were confirmed. The development application (DA) was approved in 18 weeks. Without the DBP Act's structured workflow, this level of interdisciplinary coordination would have been ad hoc and far more error-prone.
Example 3: Remedial Works on Existing Strata Building, Bondi
A strata corporation in Bondi engaged giantA to oversee remedial waterproofing and structural strengthening on a 1980s apartment building. Because the building was Class 2 and the work involved building elements, the DBP Act applied in full. We engaged a registered design practitioner — structural engineering — to prepare regulated designs for the carbon-fibre strengthening of load-bearing walls. The design compliance declaration was lodged on the NSW Planning Portal before works commenced. The strata's insurer required proof of DBP Act compliance as a condition of cover. Total project duration: 8 weeks. The lesson here is that the DBP Act applies to existing buildings, not just new developments, and insurance markets are increasingly demanding compliance evidence.
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Compliance Timeline: From Concept to Occupation Certificate
Understanding the sequence of compliance milestones helps developers build realistic project schedules. The following timeline reflects a typical medium-rise apartment development using the DA pathway.
| Phase | Activity | DBP Act Requirement | Typical Duration |
|---|---|---|---|
| Pre-DA | Concept design, site analysis, feasibility | None — but early practitioner engagement advised | 4–6 weeks |
| DA Preparation | Detailed design, BCA analysis, performance solutions | Regulated designs must be prepared by registered practitioners | 6–10 weeks |
| DA Lodgement | Submit to council or private certifier | Regulated designs and declarations lodged on Planning Portal | 2–4 weeks |
| DA Assessment | Council review, referrals, conditions | Design practitioners available to respond to referrals | 8–16 weeks |
| Construction Certificate | Final documentation, builder appointment | All regulated designs declared and lodged; builder registered | 4–6 weeks |
| Construction | Building work | Variations lodged as new regulated designs if building elements change | 12–24 months |
| Occupation Certificate | Final inspection, as-built documentation | Building practitioner lodges final compliance documentation | 2–4 weeks |
The critical takeaway is that the DBP Act adds time to the front end of a project. Developers who engage their registered design team early and treat compliance documentation as a parallel workstream — rather than a post-design afterthought — avoid the schedule blowouts that plague projects where compliance is rushed.
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Common Mistakes Apartment Developers Make
Over the past three years, we have observed recurring patterns in how developers misunderstand or mishandle DBP Act obligations. The following are the most common and most costly.
Assuming the architect handles everything. Many developers believe that engaging an architect absolves them of the need to think about practitioner registration. In reality, architectural registration and DBP Act registration are separate schemes. Your architect may be an outstanding designer but hold no DBP Act registration. You must verify both.
Treating compliance declarations as paperwork. Some developers view the design compliance declaration as a bureaucratic checkbox. It is not. It is a statutory declaration made under personal liability. If a practitioner is unwilling to make the declaration, that is a red flag about the quality or completeness of the design — not a hurdle to overcome.
Failing to budget for compliance costs. DBP Act compliance adds costs: registration fees for practitioners, additional documentation time, title block preparation, and Planning Portal lodgement. These are not enormous sums, but they are predictable, and they should be in your feasibility model from day one. A typical medium-rise apartment project will incur an additional $8,000–$15,000 in compliance-related professional fees compared to pre-2021 projects.
Ignoring variation protocols. If a design changes during construction — and most do — the amended design may require a new regulated design and a new compliance declaration. Developers who fail to account for this in their construction contracts find themselves facing unbudgeted consultant fees and potential certifier delays.
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Cost Implications and Budget Planning
The DBP Act adds direct and indirect costs to apartment development. Direct costs include practitioner registration fees, additional documentation, and lodgement fees. Indirect costs arise from the extended pre-construction timeline and the need for more rigorous design coordination.
Based on giantA's project experience in 2024–2026, the following ranges are representative for a medium-rise apartment building in Greater Sydney:
| Cost Item | Pre-DBP Act (est.) | Post-DBP Act (2026) | Variance |
|---|---|---|---|
| Design practitioner compliance documentation | Minimal | $8,000 – $15,000 | +$8,000 – $15,000 |
| Principal design practitioner coordination | Ad hoc | $5,000 – $10,000 | +$5,000 – $10,000 |
| Planning Portal lodgement and administration | $500 | $1,500 – $3,000 | +$1,000 – $2,500 |
| Extended pre-construction timeline (holding costs) | Baseline | +2–4 weeks | Varies by project |
These costs are modest in the context of a multi-million-dollar development, but they are real, and they are unavoidable. The greater risk is the cost of non-compliance: a delayed occupation certificate can add months of holding costs, and a rectification order can run into six or seven figures.
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Frequently Asked Questions
What is a regulated design under the DBP Act?
A regulated design is a formal design document — drawing, schedule, specification, or report — that addresses a building element or performance solution for a Class 2, 3, or 9c building. It must be prepared by a registered design practitioner in the appropriate class, include a standard title block, and be accompanied by a design compliance declaration lodged on the NSW Planning Portal before construction begins.
Does the DBP Act apply to renovation work on existing apartment buildings?
Yes. The DBP Act applies to all building work on existing Class 2 buildings, including alterations, repairs, and renovations, where the work involves a building element or performance solution. For existing Class 3 and 9c buildings, this obligation takes effect from 1 July 2028.
Can an unregistered architect design a Class 2 building in NSW?
No. While an architect registered under the Architects Act 2003 may prepare architectural drawings, they cannot make a design compliance declaration or prepare regulated designs for a Class 2 building unless they also hold DBP Act registration in the relevant class. Many architects do hold both registrations, but developers must verify this independently.
What happens if a developer starts construction without lodged regulated designs?
A certifier cannot issue a construction certificate or complying development certificate without confirmed lodgement of regulated designs and declarations. If construction proceeds without these documents, the Building Commissioner can issue a stop-work order, and the developer may face disciplinary action under the RAB Act. Insurance coverage may also be compromised.
How long does DBP Act compliance add to a typical apartment project?
For a well-organised developer with an experienced design team, DBP Act compliance adds approximately two to four weeks to the pre-construction timeline. For developers who treat compliance as an afterthought, delays of eight to twelve weeks are common. The key variable is the maturity of the design team's compliance workflow, not the size of the building.
What is the difference between a design practitioner and a principal design practitioner?
A design practitioner is registered to prepare regulated designs and make compliance declarations in a specific discipline — for example, building design or structural engineering. A principal design practitioner is registered to coordinate and lodge designs prepared by other practitioners. On larger projects, a principal design practitioner acts as the central compliance coordinator, ensuring that all disciplines are aligned and that declarations are made in the correct sequence.
Are there any exemptions from the DBP Act?
Yes. Certain work is excluded, including exempt development (other than waterproofing), work under the HomeBuilder Grant, and fit-out work in non-residential building classes. Specific low-risk Class 3 buildings, such as hotels and motels with no strata component, are also exempt. See Section 13 of the Design and Building Practitioners Regulation 2021 for the complete list.
How can a developer verify a practitioner's DBP Act registration?
The NSW Planning Portal maintains a public register of registered design practitioners, building practitioners, and principal design practitioners. Developers should search the register by name or registration number before engaging any consultant. The register shows the practitioner's classes of registration, expiry dates, and any disciplinary history.
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Conclusion: Compliance as Competitive Advantage
The DBP Act was born from crisis, but for disciplined developers, it offers a competitive advantage. Projects that meet the Act's requirements from the outset move through approval faster, attract better insurance terms, and command higher resale values because buyers and financiers trust the compliance record. Projects that cut corners face delays, rectification orders, and reputational damage that can take years to repair.
At giantA, we have guided numerous apartment developers through the DBP Act compliance landscape, from initial concept to occupation certificate. Our Registered Design Practitioners understand not just the letter of the law but the practical workflow of preparing, declaring, and lodging designs on the NSW Planning Portal. If you are planning a Class 2 development, we can help you build compliance into your project timeline from day one.
Contact giantA Pty Ltd for a free consultation on your next apartment development.
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Sources and References
1. NSW Government — Building classes and roles under the Design and Building Practitioners scheme (updated 6 July 2026): https://www.nsw.gov.au/housing-and-construction/compliance-and-regulation/professionals-working-on-regulated-buildings/building-classes-and-roles 2. NSW Government — Design practitioner obligations when working on regulated buildings: https://www.nsw.gov.au/housing-and-construction/compliance-and-regulation/professionals-working-on-regulated-buildings/design-and-building-practitioners/design-obligations 3. Design and Building Practitioners Act 2020 (NSW): https://legislation.nsw.gov.au/view/html/inforce/current/act-2020-007 4. Design and Building Practitioners Regulation 2021 (NSW): https://legislation.nsw.gov.au/view/html/inforce/current/sl-2021-0152 5. National Construction Code (NCC) — Building Code of Australia, Volume One: https://ncc.abcb.gov.au/ncc-navigator/building-classifications 6. Service NSW — Apply for design practitioner registration: https://www.service.nsw.gov.au/transaction/apply-for-design-practitioner-registration