The test, one question at a time
Whether a job needs a registered engineer in NSW turns on four questions, each answered by the Act or its Regulation.
Is it professional engineering work?
Section 31 defines it as “engineering work that requires, or is based on, the application of engineering principles and data to” a design, or to an engineering-related construction, production, operation or maintenance activity. Engineering work includes engineering services. It is not professional engineering work if “the work is only provided in accordance with a document that states the procedure or criteria for carrying out the work and the work does not require the application of advanced scientifically based calculations”, or if the regulations say so.
Is it in a prescribed area?
The Act names five areas: structural, civil, mechanical, fire safety and electrical engineering, plus any area the regulations prescribe (s 32(3)). The Regulation adds one: “Geotechnical engineering is prescribed” (cl 15). Building Commission NSW adds that geotechnical engineering does not include engineering that only involves geology or earth science, such as geological advice without any design and construction component.
Is it directly about a class 2, 3 or 9c building?
Clause 14 says engineering work counts as professional engineering work only if it is done directly in relation to designing or constructing a class 2, class 3 or class 9c building, or part of one. Its example: “The Act and this Regulation apply to a mixed-use building comprising class 2, class 5 and class 6 buildings, including the building’s class 5 and class 6 building parts.” Construction here includes alterations or additions, and “the repair, renovation or protective treatment of a building”.
Who is carrying it out?
Under s 32(1), the work may be carried out only by a registered professional engineer whose registration authorises it, by a person working under the direct supervision of such an engineer, or by a person the regulations authorise. Building Commission NSW puts the supervision exception this way: the supervisor must be a registered professional engineer whose registration authorises the supervisor to carry out the work.
The maximum penalty under s 32(1) is 1,500 penalty units for a body corporate, or 500 penalty units in any other case.
Unregistered work earns no fee
The Act puts a money consequence on unregistered work. If a person carries out professional engineering work in breach of s 32(1):
“(a) no monetary or other consideration is payable for the carrying out of the professional engineering work, regardless of any contract or arrangement, and
(b) an amount paid for the carrying out of the professional engineering work is recoverable as a debt in a court of competent jurisdiction.”
Design and Building Practitioners Act 2020 (NSW), s 32(2)
Insured, as a condition of the work
A registered professional engineer must not carry out professional engineering work, or hold out that they are adequately insured for it, unless they are adequately insured for the work. The maximum penalty is 300 penalty units for a body corporate, or 100 penalty units in any other case (s 33(1)). Building Commission NSW says mandatory insurance became a requirement for all professional engineers doing professional engineering work on regulated buildings from 1 July 2022. Under the Act and the Regulation, an engineer is adequately insured either by a professional indemnity policy that complies with the Regulation, or by an approved arrangement: for a member of a professional body of engineers with a professional standards scheme, or an engineer recognised or registered by a recognised engineering body, that means meeting the body’s insurance requirements (s 33(2); Regulation, clauses 69 and 70).
What engineer registration alone does not cover
Building Commission NSW says registered professional engineers can give engineering advice on a regulated building in their field, but cannot prepare regulated designs, make design compliance declarations, or lodge documents for regulated buildings unless they are also registered as a design practitioner in the relevant class. The declaration side is on an engineer’s certificate and the NCC.
Keeping registration, and coming from interstate
- A code of practice. Professional engineers must comply with a code of practice setting out professional and ethical standards; it is in Schedule 4 of the Design and Building Practitioners Regulation 2021.
- Training each year. A registered professional engineer must complete continuing professional development each year. An engineer who belongs to a professional body of engineers that runs a professional standards scheme, or who is recognised or registered by a recognised engineering body, meets this by satisfying that body’s requirements; in other cases the engineer must complete at least 50 hours of relevant education and training for the year (Regulation, Schedule 3, clause 5).
- Queensland and Victoria. Under mutual recognition, professional engineers registered in Queensland and Victoria are entitled to register in NSW without demonstrating their qualifications and experience again, but they still need to register under the Act to keep working on regulated buildings in NSW.
The register, and false claims
The Secretary maintains a register of registered practitioners, and it “is to be freely available on the internet for inspection by the public” (s 98(3)). A person must not falsely represent that they or anyone else can do anything only a registered person may do, or is a registered practitioner or registered in a particular class. The maximum penalty is 600 penalty units for a body corporate, or 300 penalty units in any other case (s 58).
The NSW Legislation version of the Act read for this guide, current from 10 June 2026, notes that it does not include amendments made by three Acts not yet commenced: the Building Legislation Amendment Act 2023 (Schedule 2.2), the Building (Approvals and Practitioners) Act 2026 and the Fair Trading and Building Legislation Amendment Act 2026. This guide has not read those Acts; check the current version on NSW Legislation before relying on it.
Queensland and Victoria define the work by area of engineering instead: see registered professional engineers in Queensland and engineer registration in Victoria. Every scheme side by side is on the comparison table.