Navigating the Building Safety Act 2022:
A Practical Guide for Fire Safety Engineers
Summary
The Building Safety Act 2022 represents the most significant overhaul of fire safety legislation in a generation. Enacted in direct response to the Grenfell Tower tragedy of June 2017, which claimed 72 lives, the Act places rigorous new duties on building owners, managers, and fire safety professionals to assess and remediate unsafe external wall systems across England.
This white paper provides fire safety engineers with a technical and regulatory framework for conducting External Wall Assessments (EWAs). We examine the scale of the challenge — with estimates suggesting over 11,000 residential buildings above 11 metres may require remediation — the limitations of existing approaches such as the EWS1 form process, and practical frameworks for compliant, defensible assessments. Drawing on case study evidence and emerging best practice, this paper sets out how MH Fire Safety Limited supports responsible parties in meeting their legal obligations, protecting lives, and restoring confidence to affected communities and property markets.
1. The Problem with Existing Buildings
1.1 The Legacy of Unsafe Cladding
The Grenfell Tower fire exposed a systemic failure in the design, specification, and oversight of external wall systems across the UK’s housing stock. For decades, cost pressures, inadequate regulatory guidance, and poor supply chain accountability allowed combustible materials — including aluminium composite material (ACM) cladding with polyethylene cores, high-pressure laminate (HPL) panels, and expanded polystyrene (EPS) insulation — to be installed on buildings occupied by thousands of residents.
The scale of this legacy problem is substantial. According to the Ministry of Housing, Communities and Local Government (MHCLG), as of early 2024, over 4,630 buildings above 11 metres have been identified as having unsafe cladding, of which remediation has been completed or started on only approximately 60%. For buildings between 11 and 18 metres in height — the so-called ‘mid-rise’ category — the problem is even less well understood, with government data suggesting tens of thousands of buildings may require assessment.
1.2 Regulatory Context: The Building Safety Act 2022
The Building Safety Act 2022 (BSA) came into force in stages from April 2023. It establishes a new regulatory framework overseen by the Building Safety Regulator (BSR), now a division of the Health and Safety Executive (HSE). Key provisions directly relevant to external wall assessment include:
• The mandatory registration and licensing of Higher-Risk Buildings (HRBs) — defined as residential buildings of 18 metres or seven storeys or more — with the BSR.
• The appointment of an Accountable Person (AP) and Principal Accountable Person (PAP) for each HRB, with statutory duties for fire and structural safety management.
• The requirement for a Building Safety Case Report, which must demonstrate ongoing management of fire and structural risks including those arising from external wall systems.
• New leaseholder protections preventing the passing of remediation costs to leaseholders in qualifying buildings, significantly increasing the financial exposure of building owners and developers.
• A 30-year retrospective developer liability period, enabling legal action against developers of buildings with historic defects.
“The Building Safety Act fundamentally changes the relationship between building owners and residents. For the first time, there is a clear, statutory duty of care that cannot be delegated away.” — Senior Fire Safety Engineer, BSR Advisory Panel
1.3 The Technical Challenge
Assessing external wall systems is technically complex. Many buildings constructed or refurbished between 1980 and 2018 have multiple layers of materials, unknown product substitutions, missing or inadequate fire-stopping, and limited as-built documentation. The destruction or loss of construction records — combined with the prevalence of value-engineering decisions made during procurement — means that intrusive inspection is almost always necessary to establish ground truth.
Furthermore, the external wall of a residential building is not a single homogeneous element. It comprises the external cladding or render, cavity barriers and fire stops, insulation products, substrate, window and door assemblies, and penetrations for services. Each component contributes to the overall fire performance of the assembly, and failure in any one element can compromise the system’s ability to contain or retard fire spread.
Diagram 1: Typical external wall assembly — annotated cross-section showing cladding, cavity, insulation, substrate and fire-stopping positions
2. Current Solutions and Their Limitations
2.1 The EWS1 Form Process
The External Wall System (EWS1) form, introduced by UK Finance and the Royal Institution of Chartered Surveyors (RICS) in December 2019, was intended to provide mortgage lenders with a standardised assessment outcome for buildings with external wall concerns. The form requires a qualified professional — typically a fire engineer or chartered surveyor — to inspect the external wall system and assign one of five ratings (A1, A2, B1, or B2) based on the level of combustibility risk.
Whilst the EWS1 process provided a necessary short-term mechanism, its limitations have become increasingly apparent:
• Scope creep: Originally intended for buildings above 18 metres, lenders began requiring EWS1 forms for buildings of all heights, creating assessment bottlenecks.
• Qualification inconsistency: The RICS qualification criteria for EWS1 signatories have been criticised as insufficiently rigorous, leading to variable quality of assessments.
• Point-in-time limitation: An EWS1 form reflects the condition of a building at a single moment and does not address ongoing management obligations under the BSA.
• Conflict of interest: In some cases, assessors have faced commercial pressure from building owners to achieve particular ratings, undermining the independence of the process.
“EWS1 was a sticking plaster on a systemic wound. It gave lenders a mechanism, but it was never designed to be the comprehensive assessment tool the market demanded of it.” — Dr. Sarah Colwell, Fire Safety Research Group (attribution requires verification)
2.2 PAS 9980:2022 — A More Robust Framework
In response to the limitations of EWS1, the British Standards Institution (BSI) published PAS 9980:2022 — the Code of Practice for the Assessment of External Wall Systems for Existing Residential Buildings. PAS 9980 provides a structured methodology for fire risk appraisal of external wall construction (FRAEW), replacing the binary pass/fail logic of EWS1 with a more nuanced, risk-proportionate approach.
The FRAEW methodology introduced by PAS 9980 requires assessors to consider the full building context — occupancy profile, means of escape, fire and rescue service access, and the interaction between external wall performance and the overall fire strategy — rather than focusing solely on the combustibility of materials. This represents a significant improvement in technical rigour, but also substantially increases the expertise and time required to complete a compliant assessment.
Diagram 2: PAS 9980 FRAEW Assessment Process — from initial desktop review through intrusive survey to risk appraisal outcome
2.3 Remaining Gaps
Despite the improvements offered by PAS 9980, significant gaps persist. There is a shortage of qualified professionals competent to undertake FRAEW assessments: the Institution of Fire Engineers (IFE) and RICS have together accredited fewer than 500 individuals nationally against the current competence frameworks, against a potential demand for assessments running into the tens of thousands. The assessor market is further constrained by professional indemnity insurance availability, with many insurers unwilling to cover external wall assessment work given the scale of potential liability.
3. Implementation Framework
Based on our experience delivering external wall assessments across a wide range of building types and ownership structures, MH Fire Safety Limited has developed a five-stage implementation framework for Accountable Persons seeking to meet their obligations under the Building Safety Act 2022.
Stage 1: Portfolio Triage and Risk Prioritisation
Before any intrusive assessment begins, Accountable Persons should establish a clear, documented picture of their portfolio. This means collating all available construction records, collating existing EWS1 forms and any prior fire risk assessment reports, and applying a consistent risk-scoring methodology to prioritise buildings for detailed assessment. Height, number of dwellings, occupant vulnerability profile, and available fire and rescue service access should all inform the triage scoring.
Stage 2: Desktop Review and Document Analysis
For each building identified for detailed assessment, a thorough desktop review should be undertaken before any physical inspection. This includes review of planning and building control records, manufacturer data sheets and fire test evidence for installed products, any available O&M manuals, and photographic records from construction or previous maintenance works. Desktop review frequently identifies specific areas of concern that can be targeted during intrusive survey, improving efficiency and reducing costs.
Stage 3: Intrusive Survey and Sampling
Physical, intrusive investigation is almost always required to confirm the composition of the external wall system to the standard needed for a PAS 9980-compliant FRAEW. Survey locations should be selected to be representative of the principal wall types present on the building, with additional locations targeted at areas of concern identified during desktop review. Cavity barriers, fire stops at floor and compartment boundaries, and penetrations for services are particular areas requiring careful inspection.
Stage 4: Fire Risk Appraisal of External Wall (FRAEW)
Drawing on the outputs of Stages 1 to 3, the qualified assessor prepares a Fire Risk Appraisal of External Wall Construction in accordance with PAS 9980:2022. The FRAEW considers the full system performance in context, applying professional judgement to arrive at a risk-proportionate outcome. The outcome is categorised on a four-point scale from ‘tolerable risk’ to ‘very high risk’, with each level carrying corresponding recommendations for remediation urgency and interim mitigation measures.
Stage 5: Remediation Specification and Programme Management
Where the FRAEW identifies a need for remediation, MH Fire Safety Limited works with Accountable Persons, contractors, and leaseholder representatives to develop a costed, programmed remediation specification. This includes preparation of tender documentation, technical oversight during works, and sign-off inspection to confirm works have been completed in accordance with specification. We also support Accountable Persons in preparing the documentation required for the Building Safety Regulator, including contributions to the Building Safety Case Report.
4. Conclusion
The Building Safety Act 2022 represents not just a legal obligation but a moral one. The failures that led to Grenfell — inadequate assessment, poor documentation, accountability gaps, and commercial pressure that overrode safety — must not be repeated. External wall assessment, carried out with technical rigour and genuine independence, is central to ensuring that the estimated millions of residents living in buildings with potentially unsafe external walls can be confident in their homes.
That challenge is significant. The shortage of qualified assessors, the complexity of many building systems, and the financial pressures on Accountable Persons all present real barriers to progress. But the regulatory framework is now in place, and the consequences of inaction — for residents, building owners, and the professionals who carry statutory responsibilities — are severe.
At MH Fire Safety Limited, we are committed to delivering external wall assessments that meet the highest standards of technical competence and professional independence. Our team of IFE-qualified and PAS 9980-competent fire safety engineers brings deep practical experience to every assessment, from initial triage through to remediation sign-off.
If you are an Accountable Person, freeholder, local authority, or housing association seeking support with external wall assessment or Building Safety Act compliance, contact MH Fire Safety Limited today. We offer an initial consultation to scope your obligations and identify the most proportionate pathway to compliance.
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