Category: Specialist underwriting · Reviewed by Tim Roche, Director · PI & Commercial · Last reviewed May 2026
A mid-sized building surveying practice in the South East signed seventeen EWS1 forms between late 2019 and the end of 2021, during the worst of the lender-driven backlog. By the time the firm came to its 2024 renewal, five of those buildings had been the subject of remediation works, two were the subject of pre-action correspondence under the Defective Premises Act, and the remaining ten sat in an uncertain category — apparently fine, but not retested. The renewal in 2024 took eleven weeks to place. The 2025 renewal took five. The 2026 renewal completed in the standard cycle, on broadly similar terms to a comparable practice that had never signed EWS1s, with the historic signatory exposure ring-fenced through a defined retroactive carve-back and a documented past-project register. The trajectory of that single firm tells the story of the broader cladding PI market between 2022 and 2026. This article sets out where the market sits now, how it got here, and what defensible cover looks like in 2026.
The External Wall System (EWS1) form was introduced by RICS in December 2019 in response to mortgage lenders’ reluctance to lend on residential buildings with combustible cladding following the Grenfell Tower fire. The form was designed as a valuation aid. A competent professional — typically a chartered fire engineer, building surveyor or chartered architect — would assess the external wall system, classify it under one of two categories with several sub-options, and sign a form valid for five years.
The intent was modest: give lenders a basis to value buildings whose external wall composition was uncertain. The reality was much wider. Within months, EWS1 had become the de facto fire safety certification for residential leasehold transactions in England and Wales. Conveyancers required EWS1s for buildings far below the original height threshold. Insurers, lenders, freeholders and leaseholders all came to rely on the form. The signatory professional bore the full weight of that reliance.
The 2020 to 2022 period saw an acute backlog. Competent professionals willing to sign EWS1s were thin on the ground; those who did sign were typically inundated with work. RICS issued multiple iterations of guidance during this period, including the December 2021 revisions that clarified scope, addressed lower-rise buildings and tightened competence requirements. The signatory population was, in retrospect, a discrete and identifiable cohort whose collective exposure would become a distinct PI underwriting class.
By 2022, the EWS1 process was supplemented by the Building Safety Act 2022’s reforms and the Department for Levelling Up, Housing and Communities’ statutory leaseholder protections. The form did not disappear, but its centrality to the system reduced. EWS1 issued between 2019 and 2022 nonetheless remain in force and remain the basis on which buildings were transacted and refinanced. The signatories of those forms remain in the underwriting frame.
The Building Safety Act introduced statutory architecture relevant to cladding PI exposure across four principal dimensions.
First, the dutyholder regime for Higher-Risk Buildings imposed Principal Designer and Principal Contractor duties for HRB design and construction. The PI underwriting implication is that a firm acting as Principal Designer on an HRB scheme is now in a defined statutory role with documented competence and information-management obligations, and any breach feeds directly into the firm’s PI exposure.
Second, the Building Safety Regulator, established within the Health and Safety Executive, exercises supervisory and enforcement powers over HRBs through their lifecycle. Gateway approvals at design, construction commencement and completion introduce regulatory decision points at which a firm’s work may be scrutinised. The implications for PI notification — particularly under the “circumstances which may give rise to a claim” notification head — are significant. See the related discussion of notification practice in Claims notification mistakes brokers see most often.
Third, the developer pledge and the Building Safety Fund created the practical funding architecture for remediation. Around fifty major developers signed the developer pledge committing to remediate life-critical fire safety defects in buildings they developed. The Building Safety Fund and the Cladding Safety Scheme provide alternative funding routes. The Recovery Strategy Unit, sitting within DLUHC’s successor department, pursues recovery from parties responsible for defective construction. Each of these routes can feed back to original design professionals through contribution and recovery claims.
Fourth, sections 116 to 125 of the BSA introduced leaseholder protections, capping qualifying leaseholders’ contributions to non-cladding fire safety remediation and prohibiting recovery of certain costs through service charges. The practical effect is that recovery pressure has shifted from leaseholders to developers, freeholders and original construction professionals.
The most consequential change for PI underwriting was the amendment to the Limitation Act 1980. BSA s.135 inserted a new s.4A into the Limitation Act, extending the limitation period for claims under section 1 of the Defective Premises Act 1972 from six years to thirty years for relevant building work completed before 28 June 2022, and to fifteen years for work completed after that date.
The retrospective thirty-year extension reactivated claims that had been statute-barred under the previous six-year regime. Residential design and construction work going back to 1992 fell within the new limitation window from June 2022 onwards. The Court of Appeal in URS Corporation Ltd v BDW Trading Ltd [2023] EWCA Civ 772 confirmed the retrospective effect of s.135 and engaged with the broader scope of duties owed to subsequent purchasers under the DPA framework. Subsequent Supreme Court consideration of related issues during 2024 has reinforced the practical breadth of the regime.
For PI underwriting, the change reshaped the exposure window for original construction professionals. A firm that designed a residential block of flats in 1998, completed in 2000, would previously have had its DPA exposure extinguished in 2006. From June 2022, that same building was within the new limitation window until 2030. The retrospective effect was instantaneous on commencement of the amendment.
The forward fifteen-year window for post-June 2022 work is also material. Most claims-made PI policies are written with retroactive dates equal to or earlier than the inception date, but the forward exposure window now substantially exceeds the typical run-off period purchased by retiring practitioners. The implications for retirement planning and run-off structuring are discussed in Run-off cover: a broker’s deep dive.
The cladding PI market in 2022 was tight to the point of opacity. Insurers writing construction professionals had absorbed substantial reserving charges for cladding exposure during 2019 to 2021. Reinsurance treaties for the construction professional class hardened materially. The combined effect was that some insurers withdrew from the class entirely, others restricted appetite to clean firms with no historic residential exposure, and the remainder applied broad exclusions or sub-limited cover.
Through 2023, the market began to differentiate. Firms that could evidence remediation programmes were progressing, that their EWS1 signatory work had been ratified through the building’s subsequent safety case, and that no notified claims had crystallised, found terms easier to secure. Firms whose past work remained in an uncertain category continued to face restricted cover.
Through 2024 and into 2025, modest softening was reported across the construction professional class. Lloyd’s syndicate results for the class showed improved combined ratios as remediation work completed and as the developer pledge funding architecture absorbed significant volumes of claims that might otherwise have been routed to original designers. The ABI’s quarterly indices reflected the broader normalisation of construction-linked PI premiums during this period.
By 2026, the market position is materially more functional than it was in 2022, but several pockets remain tight. EWS1 signatories with notified claims remain the hardest category to place. Firms acting as Principal Designer on HRB schemes face elevated underwriting scrutiny and bespoke wording requirements. Remediation designers — firms now actively designing cladding replacement and compartmentation upgrade works — sit in a discrete sub-class with its own appetite considerations. For most other construction professional firms, cover is available at reasonable but not soft terms.
Specialist brokers approaching cladding-exposed firms work with three principal risk archetypes.
The firm that designed or specified the external wall system or compartmentation when the building was originally constructed. Exposure runs through DPA s.1, contractual claims by developers or purchasers, and negligence claims by subsequent owners and occupiers. The thirty-year retrospective window under BSA s.135 makes this archetype materially more exposed than was previously the case.
Underwriters approaching this archetype focus on the firm’s past project register: which residential buildings the firm designed, when they were completed, what external wall systems were specified, whether the firm had any continuing involvement after completion, and whether any of the buildings have been the subject of remediation activity, EWS1 reassessment or claims correspondence. The expected disclosure is substantially more granular than was the case before 2022.
The firm or individual who signed EWS1 forms during the backlog period. Exposure runs through reliance claims by leaseholders, freeholders, lenders and purchasers who acted on the strength of the EWS1 classification, and through professional negligence claims where the assessment is alleged to have been deficient.
The underwriting focus is on the EWS1 portfolio: how many forms the firm signed, which buildings, what reliance was placed on contractor or installer evidence, what intrusive investigations were carried out, whether the firm’s competence framework justified the scope of the assessment, and whether any of the buildings have subsequently been reassessed with a different result. Underwriters look closely at the firm’s documentation of the EWS1 process, since the practical defensibility of the signatory’s position turns heavily on the contemporaneous record.
The firm now actively designing cladding replacement, compartmentation upgrade or other remedial works. Exposure runs forward — the work being designed in 2026 is new design liability, subject to the fifteen-year forward DPA window for work completed after June 2022.
Underwriters approaching remediation designers focus on the firm’s competence framework, the contractual architecture under which the remediation is being procured, the firm’s reliance on intrusive investigation reports, and the building safety case process. The work is regarded as higher-risk than ordinary commercial design, but it is also discretely scoped and frequently funded through structured remediation programmes that provide a degree of audit trail.
Defensible cover for a cladding-exposed firm in 2026 is characterised by explicit, documented risk allocation rather than implicit reliance on broad cover. Several features are now common to well-structured placements.
A declared past-project register, identifying residential schemes the firm has designed or assessed, with sufficient granularity to allow the insurer to model the exposure. This register is often referenced in the proposal form and forms part of the basis of the cover.
A defined retroactive date carve-back where appropriate. Where the firm has historic EWS1 signatory work or designed pre-2022 residential schemes, the policy may either preserve cover for those projects on stated terms or carve them out with reference to identified circumstances notified to a prior insurer. The interaction with the retroactive date is discussed in The retroactive date trap: a broker’s view.
A fee income split by activity type. Underwriters now expect to see the firm’s fee income broken down by activity — typically distinguishing new-build residential, remediation, EWS1 work, fire engineering, commercial design and other activities. The breakdown allows premium and exclusion structures to be calibrated to the actual exposure.
Explicit treatment of HRB scope where relevant. Where the firm acts as Principal Designer or carries out other HRB work, the policy wording will reference the statutory role and the related duties, with bespoke wording around the duty holder regime.
A structured aggregation clause. The Supreme Court’s framework in AIG Europe Ltd v Woodman [2017] UKSC 18 remains the authoritative guidance. For cladding-exposed firms, the aggregation analysis often turns on whether claims arising from a common building, a common system or a common signatory event aggregate as one. The practical implications are discussed in PI aggregation of claims explained.
A clear position on segregated reserves where the insurer requires them. Some insurers writing cladding-exposed firms expect to see ring-fenced reserves or capital allocated to historic exposure, evidenced through the firm’s financial statements or partnership accounts.
The recovery architecture under the Building Safety Act has materially changed the landscape into which PI claims are now made. The Recovery Strategy Unit, the building liability orders regime under BSA s.130 and related provisions, the developer pledge funding mechanism and the Building Safety Fund all interact with the traditional civil claims route.
Practically, this means that a PI claim against a construction professional in 2026 frequently sits within a wider recovery matrix involving the developer, the freeholder, the original contractor, the principal designer and any specialist sub-consultants. The contribution analysis is more complex than was the case under the pre-2022 regime, and the firm’s PI insurer’s interest in the wider claim structure is correspondingly stronger.
The Court of Appeal’s engagement with these issues in URS Corporation Ltd v BDW Trading Ltd [2023] EWCA Civ 772 and subsequent appellate guidance has provided some clarity on duties owed to developers by their original design professionals. Other authorities continue to refine the practical scope of the duty under the DPA and at common law. Specialist brokers monitoring this case law are well placed to anticipate how policy wordings will respond to evolving claim shapes.
The trajectory of the building surveying practice referenced at the start of this article — eleven weeks in 2024, five weeks in 2025, standard cycle in 2026 — is broadly indicative of the wider market normalisation. Cladding exposure has not gone away, but it has been absorbed into the structure of PI underwriting. The discipline now expected of cladding-exposed firms — granular project registers, declared activity splits, documented competence frameworks, explicit retroactive treatment of historic work — is the new standard for the construction professional class.
Firms that have invested in that discipline are finding renewal achievable. Firms that have not face a longer cycle and a tighter set of terms. The broker market has, for its part, developed a structured approach to placing this exposure that did not exist in 2022.
The EWS1 (External Wall System) form was introduced by RICS in December 2019 to inform lenders of the fire safety status of external wall systems on residential buildings. The forms were signed by competent professionals — typically chartered fire engineers, building surveyors or chartered architects. The 2019 to 2022 period saw a substantial backlog and an identifiable cohort of signatories who took on significant collective liability exposure through their assessment work.
Yes. BSA s.135 inserted s.4A into the Limitation Act 1980, extending the limitation period for claims under section 1 of the Defective Premises Act 1972 from six to thirty years for relevant building work completed before 28 June 2022. The retrospective effect was confirmed by the Court of Appeal in URS Corporation Ltd v BDW Trading Ltd [2023] EWCA Civ 772. Residential design work going back to 1992 is potentially within the limitation window for DPA claims.
The 2022 market was tight, with broad exclusions and restricted cover. Through 2023 to 2025, the market differentiated as remediation programmes progressed and the funding architecture under the BSA absorbed significant claim volumes. By 2026, terms are materially more functional, but EWS1 signatories with notified claims, Principal Designers on HRBs, and remediation designers remain in discrete sub-classes with bespoke underwriting treatment.
A Principal Designer for HRB design is the dutyholder appointed under the BSA to coordinate design work in relation to building safety. The role carries specific competence and information-management duties under the Act and associated regulations. Firms acting as Principal Designer on HRB schemes face elevated PI underwriting scrutiny and bespoke wording around the statutory role.
Defensible cover is characterised by explicit, documented risk allocation: a declared past-project register, an explicit retroactive date treatment of historic work, a fee income split by activity type, structured aggregation language tested against the AIG Europe Ltd v Woodman framework, and clear treatment of HRB scope where relevant. The structure allows both the firm and the insurer to model the exposure with reasonable confidence.
Yes, indirectly. Sections 116 to 125 of the BSA cap qualifying leaseholders’ contributions to non-cladding fire safety remediation and prohibit recovery of certain costs through service charges. The practical effect is that recovery pressure has shifted from leaseholders to developers, freeholders and original construction professionals, feeding back to PI insurers through contribution and direct claims routes.
Around fifty major developers signed the developer pledge committing to remediate life-critical fire safety defects in buildings they developed. The pledge funds the practical remediation but does not extinguish underlying liability claims. The Recovery Strategy Unit and other recovery mechanisms can pursue contribution from original design professionals, and PI insurers continue to engage with claims routed through the recovery matrix.
The first step is a structured review of the EWS1 portfolio: which buildings were assessed, when, on what scope, with what reliance on contractor evidence, under which version of RICS guidance, and what has subsequently happened to the buildings. The output is a project register that supports both the firm’s underwriting disclosure and the insurer’s appetite assessment. Where any building has been the subject of correspondence or reassessment, the firm should consider notification under the prior or current PI policy as a matter of priority.
Apex Insurance Brokers Ltd is an independent UK insurance broker based in Bristol, advising professional services firms on professional indemnity insurance and related covers. The firm is authorised and regulated by the Financial Conduct Authority (firm reference 724952) and registered at Companies House (company number 07014570).
This commentary reflects market conditions as at May 2026 and is provided for general information. Insurance market conditions, policy wordings and regulatory positions change frequently; firms should obtain advice specific to their circumstances rather than rely on general commentary.
Apex Insurance Brokers serves UK professional services firms and commercial businesses. Call 0117 325 0027, email hello@apexinsurancebrokers.co.uk, or request a quotation.
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