Which specified professional should you choose? Comparing the three Schedule 3 qualifications (and correcting the AP/RSE/RGE mix-up)

Schedule 3 to the Basic Housing Units Ordinance (Cap. 658) recognises exactly three categories of specified professional: a registered architect, a registered professional engineer in one of the specified engineering disciplines, and a registered professional surveyor in the building surveying division. There is no fourth category. The "Authorized Person (AP)", "Registered Structural Engineer (RSE)" and "Registered Geotechnical Engineer (RGE)" labels that landlords often hear are registration categories under the Buildings Ordinance (Cap. 123) — an entirely separate regime from Schedule 3. Searching only the AP/RSE/RGE registers will not only cause you to miss many qualified professionals; you may end up engaging someone who does not meet the Schedule 3 requirements at all, wasting both time and money. This article compares the three statutory qualifications and explains how to verify and choose.

1. First, correct a common misnomer: AP/RSE/RGE are not Schedule 3 terms

Many landlords searching for "who to engage for BHU certification" encounter advice along the lines of "you need an AP" or "choose between an RSE and an RGE." The premise itself is wrong and must be corrected first: AP, RSE and RGE do not appear in Schedule 3 to the Basic Housing Units Ordinance.

AP (Authorized Person), RSE (Registered Structural Engineer) and RGE (Registered Geotechnical Engineer) are registration categories under the Buildings Ordinance (Cap. 123), administered by the Building Authority (Buildings Department) for building plan approval, structural design and geotechnical works. The "specified professional" under the Basic Housing Units Ordinance (Cap. 658), by contrast, is defined by Schedule 3 through three registration qualifications — a completely separate regime under a different ordinance.

Why are the two so often conflated? The reason is practical: many Authorized Persons are themselves registered architects or registered engineers, and most of them also meet one of the Schedule 3 categories — though not all — so "find an AP for BHU certification" became a common shorthand. But overlap is not equivalence — holding AP registration alone does not automatically satisfy the Schedule 3 requirement. Conversely, a registered professional surveyor in the building surveying division who is not an AP at all can lawfully act as a specified professional. The correct answer to the searcher's real question — "which professional should I engage for BHU certification?" — is always the three Schedule 3 qualifications, never the AP/RSE/RGE registers.

2. The three Schedule 3 categories compared

Under Schedule 3 to the Basic Housing Units Ordinance, the following three categories of persons may act as specified professionals. All three are equally valid in law; they differ only in professional background and strengths:

1. Registered Architect (Cap. 408)

A person on the register of architects referred to in s.8(a) of the Architects Registration Ordinance (Cap. 408). Architects are trained in architecture-led design and are familiar with building layout, partitioning, lighting and ventilation, and the plan-approval culture under the Buildings Ordinance — giving them a comprehensive view when assessing the living environment of subdivided units. If a unit requires renovation to meet the minimum standards (for example, altering partition walls or adding windows), an architect can often handle both the assessment and the improvement design.

2. Registered Professional Engineer (Cap. 409; specified disciplines)

A person on the register of professional engineers referred to in s.7(a) of the Engineers Registration Ordinance (Cap. 409), in the building, building services, civil, fire or structural engineering discipline. Engineers' strength lies in engineering systems: structural safety, building services (plumbing, electrical, fire services, ventilation) and the associated calculations. If a unit's problems centre on structural alteration, fire service installations or mechanical and electrical systems, an engineer in the relevant discipline is best placed to handle them. Note that not every discipline qualifies — only the five disciplines listed above appear in Schedule 3.

3. Registered Professional Surveyor (Cap. 417; building surveying division)

A person on the register of professional surveyors referred to in s.7(a) of the Surveyors Registration Ordinance (Cap. 417), in the building surveying division. Building surveyors' daily work is precisely building condition assessment: measurement, inspection of existing conditions, checking against plans and identifying unauthorised works — the closest match to the specified professional's function of "inspecting the unit on site and assessing whether it meets the minimum standards." Schedule 3 recognises only the building surveying division — surveyors in other divisions (such as general practice or quantity surveying) are not listed.

3. Which category suits your unit?

The three qualifications are legally equivalent, and a certification report signed by any of them carries the same weight. The practical consideration is the match between professional background and the unit's condition:

• The unit requires partition alterations, new windows or layout changes — a Registered Architect with an architecture-led background is usually the best fit
• The unit involves structural safety, fire service installations or M&E systems — a Registered Professional Engineer in the relevant discipline is best placed
• The work is mainly verifying existing conditions, measuring floor area and ceiling height, and checking against plans — a Registered Professional Surveyor in the building surveying division is the most direct match

If you are unsure, the choice depends on the unit's condition — consult the relevant professionals and let them judge suitability after the site inspection. Remember: all three categories must conduct a site inspection (s.17(2)) before making any evidence-based judgment about the unit.

4. How to verify whether a person is qualified

Before engaging anyone, the landlord should proactively verify that the person is genuinely on a Schedule 3 register. The method depends on their profession:

1. Registered Architect: check the register of architects under the Architects Registration Ordinance (Cap. 408)
2. Registered Professional Engineer: check the register under the Engineers Registration Ordinance (Cap. 409), and confirm the discipline is building, building services, civil, fire or structural engineering
3. Registered Professional Surveyor: check the register under the Surveyors Registration Ordinance (Cap. 417), and confirm the division is building surveying

5. Points to note when engaging a specified professional

The following points are consistent with our companion article "Specified Professionals vs Authorized Persons (AP)" and apply to all three Schedule 3 categories:

• Confirm the Schedule 3 category and registration number, and verify it yourself on the relevant register
• Ask about BHU certification experience — professionals familiar with the application process reduce the risk of rejected submissions
• Request an itemised written quotation covering assessment, report, application follow-up and whether each is included
• Confirm the site inspection will be conducted or arranged by the professional themselves (the statutory requirement of s.17(2))
• Check for professional indemnity insurance — the report is signed in the professional's name, and responsibility comes with it

For market reference ranges of the various fees, see "BHU Certification Fee Breakdown"; this article does not repeat them.

6. Frequently Asked Questions