The Class 3 inspector shortage: Gateway capacity's hard limit

Is there really a shortage of HRB building-control officers?

Yes, but the headline needs precision. England had approximately 4,200 registered building inspectors when the House of Lords examined the regulator in 2025. That is not the available workforce for higher-risk buildings. Registration is divided by class and scope. Class 2 inspectors can undertake much non-HRB work; Class 3 inspectors undertake specialist functions, including higher-risk building work, within BSR-led multidisciplinary teams.

In its May 2026 resource data, BSR called Class 3 registered building inspectors its scarcest professional resource. The regulator's August release then reported a broad support model: 176 internal staff and 506 external specialists, including 221 RBIs, 111 fire-service professionals and 135 structural engineers. Only part of that resource was fully integrated into the Innovation Unit and remediation team.

The issue is therefore not a simple national headcount. It is the supply of people with the right class, competence scope, current experience and availability to work inside an HRB multidisciplinary assessment when the case requires them.

What does Class 3 actually mean?

The Building Inspector Competence Framework defines registration classes and the work an inspector may undertake. For HRBs, Class 3 inspectors operate as part of a multidisciplinary team under BSR's direction. Class 3H denotes competence for all building types, including HRBs; narrower Class 3 categories may carry defined limits.

This is why “a Level 3 officer signs the building off” is poor language. The BSR is the building control authority. Its decision draws on registered inspectors, fire and structural expertise, case management and, where required, other specialists. No single professional certificate substitutes for that statutory decision.

The distinction also protects professional accountability. Registration confirms an assessed scope of competence; it does not make one inspector competent to decide every fire-engineering, structural, façade, services and human-factors question in a complex tower.

How did the shortage become a regulatory bottleneck?

The profession entered the new regime with an ageing workforce, uneven local-authority capacity and a history of competition between public and private building control. The post-Grenfell reforms then introduced individual registration, competence assessment and enforceable professional standards. Those controls were necessary, but the transition exposed how much system capacity had depended on experience that was not yet formally assessed to the new framework.

Evidence to the House of Lords described experienced inspectors leaving during the transition. At the same time, HRB work began demanding a deeper multidisciplinary review, while remediation, new-build, internal-work and transitional caseloads competed for the same scarce specialists. Fire engineers and structural engineers are part of the same capacity equation; an available RBI does not create an MDT if another critical discipline is missing.

Will the £70 million funding solve it?

The March 2026 package is material: £55 million for building control and £15 million for fire engineering. Government says it can support up to 700 new RBIs, fund local authorities to recruit and train to Class 2, and upskill existing inspectors, including many towards Class 3H. Fire-engineering bursaries and education capacity address the adjacent shortage.

It is not an immediate release valve. Competence in safety-critical regulatory work is not produced by a short course. New entrants need education, supervised practice, portfolio evidence, assessment and exposure to complex cases. Experienced Class 2 inspectors may progress faster, but employers must still release them for training while maintaining today's service.

The intervention should be judged over three horizons: retention now, productive upskilling over the next one to three years, and a sustainable graduate and vocational pipeline beyond that. Publishing numbers trained without numbers retained, registered and deployed on HRBs would overstate success.

What does the shortage mean for an HRB programme?

Resource risk is not a justification for an incomplete submission. It is the reason to make assessor time easy to use. A regulator with scarce specialist hours will move more predictably through information that is structured, cross-referenced and explicit about its compliance argument.

Clients should carry a regulatory programme allowance based on current performance, not the bare statutory period. Principal designers should map requirements to evidence and close interdisciplinary interfaces before submission. Contractors should preserve the approved design baseline and raise controlled changes early. All parties should distinguish elapsed time from regulator working time when further information is requested.

There is also a procurement implication. Private advisers can improve an application, but they cannot sell influence over BSR or guarantee approval. Check the individual's registration class and scope on the public register, clarify whether advice is design, building-control consultancy or independent assurance, and avoid language suggesting that a former regulator can “sign off” the scheme privately.

What should the professions ask next?

The useful questions for RICS, CIOB, RIBA and ICE members are measurable ones:

• How many inspectors hold each Class 3 scope, and how many full-time-equivalent days are available for HRB work?
• What are attrition and retirement rates by class?
• How many funded trainees reach registration, and how long does progression take?
• How is assessment consistency tested across internal and external multidisciplinary teams?
• Does faster throughput reflect stronger applications, more capacity, changed triage or a different case mix?
• Where will Gateway 3 inspection demand displace Gateway 2 assessment capacity?

The August figures show operational improvement, not surplus capacity. New-build approval reached 91%, yet BSR still described resource expansion as necessary and Gateway 3 demand is beginning to rise. The hard policy problem is no longer whether the regime needs competent inspectors. It is how to expand the profession without lowering the competence threshold the regime was created to enforce.