Design and Building Practitioners Act 2020 (NSW): registration, declarations and the statutory duty of care

What the Act does

The Design and Building Practitioners Act 2020 (NSW) regulates how Class 2 residential building work is designed, declared and built. It was passed in response to high-profile building defect failures (Opal Tower, Mascot Towers) and the broader recognition that residential apartment construction in NSW had a quality assurance gap that the statutory warranties under the Home Building Act could not close on their own.

The Act has been in force since 1 July 2021. It introduces three concrete mechanisms: registration of design and building practitioners with the NSW Building Commissioner, compliance declarations made at design and construction stages and a statutory duty of care that applies retrospectively to buildings less than 10 years old.

What buildings the Act applies to

The Act applies to Class 2 buildings under the National Construction Code: buildings containing two or more sole-occupancy units that are each separate dwellings (typically multi-storey apartments). It also applies to buildings that contain a Class 2 component, such as residential apartments above a retail or office podium.

The Design and Building Practitioners Regulation 2021 has progressively extended the scope to cover additional classes of building work. Anyone working on building types other than pure Class 2 should check the current Regulation for the up-to-date scope before assuming the Act does not apply.

Registered practitioners

The Act creates registration categories for design practitioners, principal design practitioners, building practitioners and professional engineers. Each category has its own competency requirements covering qualifications, experience and professional indemnity insurance. Registration is administered by NSW Fair Trading on behalf of the NSW Building Commissioner.

A design practitioner is someone who prepares regulated designs for Class 2 building work. A principal design practitioner coordinates the work of multiple design practitioners on a project. A building practitioner is the head contractor responsible for delivering the building work. A professional engineer is registered for the engineering work involved (structural, civil, fire safety, electrical or mechanical).

Registration is required to do any of the regulated activities on a covered project. Performing the work without registration is an offence.

Regulated designs

A regulated design under the Act is a design prepared for a critical building element or a performance solution for building work. Critical building elements include fire safety systems, waterproofing, load-bearing components, the building enclosure (facades and roofs) and essential mechanical, plumbing and electrical services.

Designs that touch any of these elements must be prepared by a registered design practitioner. The practitioner must declare the design's compliance with the National Construction Code and other applicable standards before the design is used for construction.

Compliance declarations

Section 9 of the Act requires a registered design practitioner to make a design compliance declaration each time they provide a regulated design in a form suitable for construction. The declaration confirms the design complies with the National Construction Code, applicable standards and any Regulation requirements. Declarations are lodged on the NSW Planning Portal where they form part of the permanent project record.

Building practitioners make analogous building compliance declarations at the completion of the building work. The declaration confirms the work was carried out in accordance with the regulated designs and that any design variations were themselves declared.

The compliance declaration regime creates a paper trail that the NSW Building Commissioner can audit and that becomes evidence in any later dispute about design or construction quality.

Statutory duty of care under section 37

Section 37 imposes a statutory duty on any person who carries out construction work to exercise reasonable care to avoid economic loss caused by defects. This is a significant expansion of the common law because it overrides the traditional rule that pure economic loss is generally not recoverable in negligence from construction professionals.

The duty applies to designers, builders, project managers, engineers and anyone else carrying out construction work. It is owed to the current and subsequent owners of the building. The duty applies retrospectively: it covers buildings less than 10 years old as at 10 June 2020 (when the Act commenced).

The practical consequence is that owners of Class 2 buildings (and any other class to which the Act applies) can sue any party in the construction chain for negligent work that caused economic loss, without needing a contract with that party. This routes around the privity-of-contract limitation that previously shielded subcontractors and consultants from direct owner claims.

NSW Building Commissioner powers

The Act gives the NSW Building Commissioner broad enforcement powers, including audit and investigation rights, the power to issue prohibition orders that prevent the issue of an occupation certificate and the power to refuse or revoke practitioner registrations. Prohibition orders have become a particularly active tool. The Commissioner has used them to stop occupation certificates being issued on apartment buildings with serious defects until rectification is completed.

Practical implications

For builders and designers working on Class 2 projects, the Act requires registration in the relevant practitioner category with current professional indemnity insurance. It requires working only on regulated designs prepared and declared by registered design practitioners. It requires making and lodging the prescribed building compliance declaration at completion. It requires tracking and declaring any design variations during construction. It requires maintaining records sufficient to defend against a future statutory duty of care claim.

For developers commissioning Class 2 work, the Act effectively means engaging registered practitioners is the only viable route. Unregistered work on a Class 2 project exposes the developer, the unregistered practitioner and the project as a whole to enforcement action and to prohibition orders that delay occupation.

Related entries

The DBP Act overlaps with the Home Building Act 1989 in residential building work generally. Statutory warranties under HBA section 18B and the section 18E time limits apply alongside the DBP Act duty of care; see the statutory-warranties entry. Builder licence classes under the Home Building Act continue to apply to the contractor licence side of Class 2 work; see the builder-licence-classes entry. The practical-completion-handover entry covers when the work is treated as complete for statutory purposes.