Building safety: A distinct regime for Wales

On 10 March 2026, the Senedd passed the Building Safety (Wales) Bill (the Bill), marking a significant reform to residential building regulation in Wales. The Bill forms part of the Welsh Government’s response to the Grenfell Tower tragedy, but takes a distinct approach from that adopted in England under the Building Safety Act 2022 (the BSA).

Taken together with the Building (Higher Risk Buildings Procedures) (Wales) Regulations 2025 (the Regulations), due to come into force on 1 July 2026, Wales is implementing a comprehensive building safety regime spanning design, construction and occupation. While the Welsh framework broadly mirrors England’s regime,introducing duty holders, gateway approvals and golden thread principles, there are important differences in scope that you need to be aware of.

At the occupation phase, the Bill establishes an entirely new statutory safety regime for multi occupied residential buildings regardless of height, reflecting a policy decision that building safety risks are not confined to high rise development. At the design and construction stages, the Regulations introduce a staged approval regime for higher risk buildings (HRBs), overseen by local authorities rather than a central regulator.

As a result, the Bill and the Regulations embed building safety across the entire building lifecycle and if you develop, own or manage residential buildings in Wales, you need to prepare.

The enforcement body

Under the Bill, oversight and enforcement sit with local authorities and fire safety authorities acting jointly as the Building Safety Authority. This localised enforcement model contrasts with England’s centralised approach, where responsibility for HRBs rests with the Building Safety Regulator (BSR) within the Health and Safety Executive.

A similar distinction arises under the Regulations. In Wales, local authorities will determine HRB control applications and supervise compliance with gateway approvals and golden‑thread requirements during construction. In England, by contrast, those functions are exercised by the BSR. The Welsh approach reflects a preference for embedding safety oversight within existing local regulatory structures, albeit with the potential consequence of variation in approach and resourcing between authorities.

What buildings are covered?

The Bill applies to any building that is wholly or mainly in Wales and contains two or more residential units, subject to limited statutory exclusions. While certain categories (such as secure residential accommodation, armed forces buildings, hospitals, care homes and schools) are excluded, the overall scope is expansive. As a result, many lower‑rise buildings that would sit entirely outside the English occupation‑phase regime are captured in Wales, including converted houses, student accommodation and the residential elements of mixed‑use developments.

The Regulations adopt complementary scope to those in effect in England. They apply only to higher‑risk buildings at the design and construction stage – defined broadly as buildings at least 18 metres or seven storeys high and containing at least one residential unit, one hospital bed for overnight stays, a care home or a children’s home. Notably, the Welsh definition is broader than its English equivalent, requiring only one residential unit, meaning more schemes will fall within the enhanced building control regime during construction.

Categorisation of buildings under the Bill

To mitigate the impact of its broad scope, the Bill introduces a three‑category system of regulated buildings for the occupation stage based on height and storeys. Category 1 buildings are those at least 18 metres in height or with seven or more storeys (i.e. the HRBs under the BSA). Category 2 buildings are those which are not Category 1 but are at least 11 metres in height or have five or more storeys. Category 3 buildings are those under 11 metres in height or with fewer than five storeys. Building safety risks in relation to Category 1 or 2 buildings means either fire safety or structural safety risks and in relation to Category 3 buildings, fire safety risks only.

Accountability and duties

The concepts of Accountable Person (AP) and Principal Accountable Person (PAP) broadly align with those under the BSA. An AP is a person with a legal estate in, or repairing obligations for, the common parts of a building, with the PAP being the AP responsible for the building’s external structure. The critical difference lies in where these roles arise. In England, AP and PAP obligations attach only to HRBs. In Wales, they extend to all regulated buildings as explained above, albeit to differing degrees across Categories 1, 2 and 3. This significantly increases the regulatory footprint of the Welsh regime and expands the compliance burden for landlords and managing agents.

Category 1 buildings are subject to the most extensive duties, closely mirroring the English higher‑risk framework, including registration, safety case reporting, building safety certification and enhanced resident engagement. Category 2 buildings must be registered and are subject to fire and structural safety duties, but without safety case reporting or certification. Category 3 buildings are regulated primarily through fire safety, although APs and PAPs must still assess and manage risks, maintain information and engage with residents.

What are the practical implications?

If you’re involved in residential development in Wales, the combined effect of the Bill and the Regulations is to impose end‑to‑end building safety governance that applies to a much wider range of buildings than in England.

A. Construction and the Regulations

If you’re a developer, you’ll need to build the Welsh gateway approval process under the Regulations into your programme and procurement strategies for higher‑risk buildings (HRBs) at the design and construction stage.

While the Regulations allow you to secure approvals in stages, which can give you some flexibility, this also means you’ll need careful sequencing and early engagement with local authority building control.

The key differences you need to be aware of under the Regulations include:

Definition of a HRB: In Wales, more schemes will fall within the enhanced building control regime during construction.

Building control authority: HRB applications will be determined by the local authority, rather than the BSR. The Regulations set out in greater detail what constitutes Category A work, including clear parameters around active and passive fire safety measures and the supporting material that must accompany an application.

Staged approvals and programme management: While both regimes operate gateway‑style controls, the Welsh Regulations expressly allow approvals to be granted for stages of work, often subject to limits on how far construction can progress without further approval. This has direct implications for construction sequencing and programme planning.

Statutory determination timeframes: The Welsh regime sets clear statutory timescales for building control approval (12 weeks for new HRB work and 8 weeks for work to existing HRBs) equivalent to that under the English regulations.

Local authority‑led golden thread compliance: Although the golden thread requirements broadly mirror those in England, oversight in Wales sits with local authorities. And the Welsh regime operates on a fully digital basis, with all applications and supporting information required to be submitted and managed electronically.

The Applicant: Under the Welsh regime, the concept of the “applicant” expressly extends beyond the individual submitting the application to include the client, reinforcing a broader approach to accountability.

Handover Requirements: Unlike in England, there’s no requirement to provide handover information to both an accountable person and a responsible person on completion of HRB work.

B. The Bill and occupation

If you’re a landlord or investor, you must now map your Welsh portfolios to identify which buildings fall within Categories 1, 2 and 3 and where AP and PAP roles arise. The emphasis on accurate building information and ongoing risk management means that decisions taken during construction, particularly around design changes, specifications and document control, will have lasting implications for compliance during the occupation stage.

From a transactional perspective, if you’re acquiring or disposing of residential assets in Wales, you’re likely to face more extensive due diligence. You’ll need to verify registration status, review safety assessments and engage directly with local enforcement authorities.

As regulation is increasingly localised, you may also see greater variation in how the regime is enforced. That makes early engagement with local authorities an important step in managing risk and avoiding delays to your transaction

How can we support you?

While Wales has adopted familiar building safety concepts to those in effect in England, it’s chosen to apply them through a broader, locally administered framework that extends across much of the residential sector. By aligning enhanced design‑and‑construction controls for higher‑risk buildings with a graduated, occupation‑phase regime covering low and mid‑rise buildings, the Welsh Government has embedded building safety into the routine lifecycle management of residential buildings beyond only HRB buildings.

If you’re a developer, landlord or investor, you need to develop different English and Welsh specific compliance strategies. The reforms signal a long‑term shift towards robust universal residential building safety accountability in Wales.

Our BSA experts are uniquely placed to help you to successfully navigate all of the legal, regulatory and practical changes brought about by the Bill.

Our BSA expertise and horizon scanning includes long-standing experience and success in providing strategic risk management, transactional and dispute resolution advice for industry participants in all areas of the sector, and has contributed to our in-depth understanding of all parties’ commercial perspectives.

If you have any queries in respect of the upcoming changes, please contact Alex Jones or Ibrahim Alyas.

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