Read this alongside the master Professional Indemnity Claims Handbook. This addendum covers architectural practices in the UK regulated by the Architects Registration Board (ARB) and (typically) chartered with the Royal Institute of British Architects (RIBA). Where there is conflict, the ARB Code, the relevant building safety legislation and any specific policy wording prevail.
1. The regulatory landscape — in plain English
UK architectural practice is regulated by two bodies, doing different jobs:
ARB — statutory regulator under the Architects Act 1997. Registration is mandatory for anyone calling themselves “architect.” The ARB Code (currently the ARB Architects Code of Conduct and Practice) sets standards. PI insurance is a registration condition. See arb.org.uk for the current Code and minimum cover guidance.
RIBA — professional body. Chartered membership is voluntary, but RIBA’s Code of Practice imposes additional standards on its members. RIBA Insurance Agency (and other markets) provide compliant PI cover.
In parallel, the Building Safety Act 2022 and the Higher-Risk Buildings (Key Building Information etc.) Regulations 2023 have materially reshaped responsibilities and liabilities for buildings within scope. The retrospective limitation extension to 30 years (for dwellings under section 135 of the Building Safety Act, amending the Defective Premises Act 1972) is the single most significant change to architectural PI exposure in a generation.
2. Notification cascade — architects-specific
In addition to the cascade in the master handbook:
ARB notification: Under the ARB Code, registered persons must notify ARB of certain matters — including PI matters in some circumstances. The ARB’s notification expectations should be checked on a current basis at arb.org.uk; the threshold is not the same as the PI policy threshold.
Principal Designer dimension: Where the practice acts as Principal Designer under the Building Safety Act regime (for higher-risk buildings) or under the CDM Regulations 2015 (for construction generally), regulatory dimensions multiply.
Building Safety Regulator (BSR): For higher-risk buildings, BSR is the relevant building control body and has enforcement powers. A circumstance touching a higher-risk building should be assessed for BSR engagement.
Local Authority Building Control / Approved Inspector: Routine but worth keeping in scope.
Build the notification map at the start of the matter. Apex will help; specialist construction-regulatory counsel is sometimes essential.
3. The typical claim patterns we see in architects’ PI
Buildability — design that cannot be built within budget or programme; contractor claims onto designer.
Performance — completed building does not meet stated performance (thermal, acoustic, etc).
3.2 Building safety and cladding
Since Grenfell, this is a sector-defining category. Claims patterns include:
External wall systems alleged non-compliant under Approved Document B or under the relevant version at design time.
Compartmentation failures — design intent vs as-built.
Fire stopping coordination — Principal Designer responsibility for design coordination.
Pre-2017 designs revisited — the 30-year limitation extension under section 135 of the Building Safety Act 2022 has retrospectively widened exposure for dwellings.
Class action and group claim activity — multiple owners in a block aggregating claims; aggregation language in the policy becomes acutely important.
3.3 Contract administration
Certification errors — interim certificates, practical completion certificate, certificate of making good — that bind clients in ways they did not expect.
Extensions of time — granted or refused incorrectly.
Specification clarification — instructions to contractor that change scope.
Final account — disputes that draw the architect in.
Boundary, party wall, and rights of light failures to identify.
3.5 Conservation and heritage
Listed building works without proper consent.
Heritage damage during construction.
3.6 Master-planning and feasibility
Capacity studies that prove unrealistic.
Feasibility cost estimates that prove materially low.
4. The Building Safety Act dimension — what’s different
For higher-risk buildings (HRBs) — broadly residential buildings of at least 18m or 7 storeys, plus certain hospitals and care homes — the BSA regime imposes additional obligations through three duty-holder roles (Client, Principal Designer, Principal Contractor) and through the new building control regime via BSR.
Practical implications for PI:
30-year limitation for DPA 1972 claims on existing dwellings, applying retrospectively. The market is still working through what this means commercially.
Gateway approvals under BSR — failure or delay at any gateway creates loss and dispute.
Golden thread — information management requirements; failure to maintain creates evidence problems in claims.
Higher reserves — insurers reserve more cautiously on HRB-affected matters; this affects firm renewal even on closed-nil matters.
Most PI policies have, by 2026, evolved their language around BSA exposure — sometimes via specific exclusions, sometimes via sub-limits, sometimes via aggregation re-statements. Read your wording. Apex will help.
5. Worked examples
5.1 Worked example: post-completion cladding query
Client commissioned a 6-storey residential block, completed 2018. In 2026 the management company commissions an EWS1-style review which raises questions about a section of the rainscreen system. The management company writes to the architect-of-record (Apex client) demanding contribution to remediation.
Apex client response:
Day 1: Letter received. Risk director consulted same day. Litigation hold issued — specifically including project archives, BIM models, drawings registers, NBS specifications, fire engineer correspondence.
Day 1: Holding response — neutral.
Day 2: Apex notified. Insurer notified in writing with the demand letter and the engagement appointment.
Day 3: Panel solicitor instructed (typically a construction specialist familiar with EWS / BSA matters).
Weeks: Forensic survey of the actual installation; comparison with specification at design; coordination with fire engineer; contribution analysis with contractor and sub-contractors.
Outcome (illustrative): contribution claim moderated by design specification record; settlement allocated by tribunal or mediation; matter takes 18–48 months.
Key point: the strength of the design record — what was specified, what assumptions were made, what was inspected — is decisive.
5.2 Worked example: design review gateway failure
Client (housebuilder) alleges that delays through the BSA Gateway 2 process were caused by inadequate fire strategy documentation, with consequent demobilisation and re-mobilisation costs.
Apex client response:
Day 1: Client letter received; initial commercial discussion logged.
Day 1-2: Risk director escalates; Apex notified; hold issued.
Day 3: Insurer notified; panel solicitor consults on BSA-specific causation.
Subsequent: technical defence based on fire engineer’s separate role; client contributory issues; programme analysis.
5.3 Worked example: design coordination — services in structure
A commercial fit-out by Apex client. Two years post-completion, the tenant discovers that MEP penetrations have been formed through a primary structural element. Remediation requires temporary works.
Apex client response:
Day 1: Tenant letter received via building owner.
Day 1: Hold; Apex notified.
Day 2: Written notification; panel firm engaged; structural engineer (also Apex client or separate party) brought into the matter.
Outcome: contribution analysis between architect, structural engineer, MEP designer and contractor. Apex coordinates if multiple insureds are Apex clients (with conflict management).
6. Engagement and appointment discipline — architect-specific
RIBA Standard Professional Services Contract or equivalent: signed, current, in the file.
Scope of services: clear; aligned to RIBA Work Stages or equivalent.
Fee basis: clear; aligned with scope.
Sub-consultant coordination: who appoints whom; net contribution / contribution apportionment.
Liability cap: where the form permits — and where the client will agree.
Net contribution clause: critical for limiting liability where multiple designers contributed.
Reliance and assignment: who can sue you; over what period.
Copyright and licence: keeps the practice’s IP separate from the client’s relationship.
The Risk Toolkit goes into detail. The headline: architects who use bespoke or amended appointment forms (rather than the standard RIBA or other industry forms) need their wording PI-reviewed at point of execution, not at point of claim.
7. Collateral warranties — the architect-specific exposure multiplier
Architects frequently sign collateral warranties to lenders, tenants, funders and purchasers. Each warranty extends the population of potential claimants, often without extending the policy limit. Practical points:
Standard industry warranties (e.g. CIC, BPF forms) are normally manageable.
Bespoke warranties drafted by funder’s lawyers should be reviewed against your appointment — they should not impose duties wider than the appointment.
A “no greater duty than appointment” clause should appear.
A “net contribution” clause should appear.
Limitation should be aligned with appointment (typically 12 years for deeds), and not extended without thought.
Collateral warranty signatures should be logged centrally — at claim time you need to know quickly who you have given warranties to.
8. Apex’s role in architects’ PI claims
Within the constraints of the master handbook:
We are familiar with the ARB minimum cover guidance, the current major architect-focused PI wordings (RIBA Insurance Agency and others), and BSA-driven market changes.
We can introduce specialist construction-regulatory counsel.
We coordinate where multiple Apex clients are co-defendants (with proper conflict management).
We will engage on run-off, sale-of-practice, and successor practice issues, which are increasingly common in the architects’ market.
We will help map collateral warranty exposure.
9. Common architect-specific pitfalls
The signed appointment that nobody can find. Centralise.
Variation by email, not formalised. Variation of scope must be papered.
BIM model versioning unclear. Make sure the model state at each stage is preserved.
Site visit notes that “weren’t really inspection.” Inspection records, even informal ones, are disclosable.
Email “design clarifications” to contractor. Treat as instructions; expect them to be relied upon.
Old projects that touch HRBs. Audit your back catalogue for HRB exposure; refresh records before challenge.
10. Apex client checklist for architects
[ ] We have a named risk director and deputy.
[ ] We have a written internal circumstance escalation procedure.
[ ] We have current Apex client services contact details.
[ ] We have current and prior policy schedules accessible.
[ ] We have a litigation hold template ready.
[ ] We have an evidence inventory map (CAD, BIM, document management, email, drawing register, model register, site notes, mobile).
[ ] We have a collateral warranty register.
[ ] We have specialist construction-regulatory counsel on speed dial.
[ ] We review our claims history annually with Apex.
[ ] We have audited our back catalogue for HRB exposure.
[ ] Run-off arrangements are planned ahead of any closure / sale / merger.
Apex Insurance Brokers Ltd is authorised and regulated by the Financial Conduct Authority. FCA Firm Reference Number 724952. Registered in England and Wales, company number 07014570. Registered office: Bristol, United Kingdom. This document is provided to Apex clients as a general guide. It is not legal advice and is not a substitute for the terms of your insurance policy. Always read your policy schedule and wording. If you have a circumstance or claim, contact Apex without delay.
Our service promise. We acknowledge every quote request the same working day. For straightforward risks, indicative terms typically follow within five working days. Complex risks — higher-risk buildings, cladding, mid-term proposals requiring fresh underwriting — may take longer; we’ll send you a progress note by the end of the fifth working day in those cases.