RPEQ Engineer or Building Inspector: Who Signs What in Queensland

Two Different Roles, Two Different Statutes

Building inspectors and RPEQ structural engineers both visit buildings, both produce written reports, and both charge fees. Beyond that, the similarity dissolves. They are authorised under different legislation, they carry different professional obligations, and their documents mean different things to a certifier, a court, or an insurer.

Queensland building inspectors operate primarily under the *Building Act 1975* and the *Queensland Building and Construction Commission Act 1991*. Their role is to identify visible defects, assess workmanship against the relevant standard, and report what they observe. A licensed building inspector can produce a pre-purchase inspection report or a defect notice. What they cannot do is certify structural adequacy. That function sits elsewhere.

An RPEQ structural engineer is registered under the *Professional Engineers Act 2002* (Qld). Registration requires demonstrated competency in a nominated area of practice, continuing professional development, and personal liability for engineering judgements. When an RPEQ signs a document, that signature carries statutory weight that a building inspection certificate does not.

What Form 15 Actually Certifies

Form 15 is a certificate of inspection issued under the *Building Regulation 2021* (Qld). It is the mechanism by which a competent person confirms that inspectable work complies with the relevant approval. For structural elements, the competent person must be an RPEQ or a person with equivalent standing.

The certificate is not a statement that a building looks acceptable. It is a professional declaration that the work meets the structural requirements of the approval, the applicable Australian Standards, and where relevant, the National Construction Code. The RPEQ signing a Form 15 is attaching their registration to that claim. If the claim is wrong, the consequences are professional, financial, and potentially legal.

This is why certifiers request Form 15 from an RPEQ rather than from a building inspector. The certifier is not being pedantic. They are managing their own statutory exposure under the *Building Act 1975* and the *Building Regulation 2021*. A building inspector's report does not discharge that exposure. An RPEQ's Form 15 does.

The Inspection Report Versus the Investigation File

A standard building inspection report documents what is visible at the time of inspection. It lists cracks, spalling, staining, deflection, and other observable conditions. For pre-purchase due diligence or a general condition overview, that is a reasonable product.

It is not, however, an investigation file.

An investigation file answers different questions. How far does the defect extend below the surface? What is the residual section thickness of a corroded reinforcing bar? Has carbonation reached the steel? Is the crack active or dormant? These questions require non-destructive testing, material sampling, and in some cases NATA-certified laboratory analysis. They require an engineer who can interpret the results against structural mechanics and the relevant Australian Standards.

The distinction matters most when a strata committee or building owner is deciding whether to spend money. A building inspection report that lists twenty defects tells you there are twenty defects. It does not tell you which three require immediate action, which twelve can be monitored over two years, and which five are cosmetic. Without that classification, remediation contractors price the worst case across all twenty. The budget blows out before a single piece of concrete is touched.

This is the gap that structured engineering investigation closes. Quantifying the extent and severity of each defect, rather than simply identifying it, is what converts a list of problems into a capital plan.

Where Building Certifiers Sit in This Framework

Private building certifiers in Queensland are licensed under the *Building Act 1975* and regulated by the Queensland Building and Construction Commission. Their function is to assess whether building work complies with the approval and the relevant codes. They are not structural engineers, and they do not hold RPEQ registration.

When a certifier encounters a structural question they cannot resolve from the drawings and specifications alone, they refer it to an RPEQ. That referral is not a sign of weakness. It is the correct process. The certifier's role is to administer the approval framework. The RPEQ's role is to certify structural adequacy. Neither role substitutes for the other.

Problems arise when this boundary is blurred. An owner who presents a building inspection report to a certifier in lieu of an RPEQ Form 15 is presenting the wrong document. A strata committee that relies on an inspection report to satisfy a certifier's structural query is likely to receive the same request again, worded more firmly.

Certifiers who understand this boundary tend to specify what they need precisely: Form 15, signed by an RPEQ, covering the nominated inspectable items. Owners and strata committees who understand it can prepare accordingly, rather than cycling through multiple reports that do not answer the question.

Existing Buildings and the Complication of Age

The *Professional Engineers Act 2002* applies to engineering services, not just new construction. When an RPEQ is engaged to assess an existing building, the same professional obligations apply. The engineer must form a view on structural adequacy based on evidence, not assumption.

For older Queensland buildings, this creates specific challenges. Structures built before the 1990s may predate current Australian Standards for earthquake actions, wind loading, or concrete durability. The drawings may not exist. The concrete mix design is unknown. Reinforcement cover was not consistently specified or inspected under older regimes.

In these situations, an RPEQ cannot simply inspect visually and sign off. The investigation needs to establish what the structure actually is, not what the drawings say it should be. That means cover meters, carbonation testing, half-cell potential surveys, core sampling, and compressive strength testing. It means comparing the results against the current NCC performance requirements and determining whether the existing structure meets them by reference to evidence rather than documentation.

A building inspector working under the *QBCC Act* is not equipped or authorised to do this work. The statutes are different. The required competency is different. The output is different.

Liability and Who Carries It

Professional liability follows the document. If an RPEQ signs a Form 15 and the structure subsequently fails in a manner consistent with what was certified, the RPEQ carries professional liability under the *Professional Engineers Act 2002* and potentially under the *Civil Liability Act 2003* (Qld). Their professional indemnity insurance responds to that liability.

A building inspector who produces a report under the *QBCC Act* carries liability for that report, within the scope of what the report claims to cover. If the report does not claim to assess structural adequacy, it does not create liability for structural adequacy. This is not a criticism of building inspectors. It is a description of how the liability framework operates.

Owners and strata committees should read the scope of any report they receive before deciding what it tells them. A report that states it is a visual inspection of accessible areas, conducted in accordance with AS 4349.1, is telling you exactly what it covers. Structural adequacy of concealed elements is not in that scope.

Practical Guidance for Owners, Strata Committees, and Certifiers

For building owners and strata committees:

• If a certifier has requested a Form 15, engage an RPEQ. A building inspection report will not satisfy the request.
• If you have received a defect report and are planning remediation, ask whether the report quantifies extent and severity or only identifies visible conditions. The answer determines whether you have enough information to budget accurately.
• If your building is more than twenty years old and you have not had a structural condition assessment by an RPEQ, the inspection report in your files is not a substitute for one.

For certifiers:

• When specifying what you need from an owner, name the document and the required signatory. "Structural certification from an RPEQ" is unambiguous. "Engineer's report" is not.
• If you receive a document that does not match what you requested, return it with a clear explanation of the gap. This protects you and accelerates the process for the owner.

The Signature Matters Because the Statute Matters

Queensland's building regulatory framework assigns specific functions to specific licence classes and registration categories for a reason. The *Professional Engineers Act 2002* exists because structural adequacy is a technical question with safety consequences, and the community needs a mechanism for holding engineers accountable for their answers.

A Form 15 signed by an RPEQ is that mechanism in practice. It is not a formality. It is a professional declaration backed by statutory registration, supported by an investigation file, and attached to the engineer's ongoing obligation to practise competently.

If you are working through a certification process, a defect assessment, or a capital works decision and you are uncertain which professional you need and what document they should produce, TRSC engineers hold RPEQ registration across Queensland, New South Wales, and Victoria. More information is available at [https://trsc.au](https://trsc.au).