Committee publication · Correspondence · 12 January 2026

Letter from the Chief Executive Officer of the Installation Assurance Authority Federation relating to the Committee’s evidence session on 13 November 2025 on Faulty energy efficiency installations, 23 December 2025

From: Public Accounts Committee

Inquiry: Faulty energy efficiency installations

Summary

The Installation Assurance Authority Federation's CEO writes to challenge testimony given by TrustMark's Chief Executive at the 13 November 2025 evidence session on faulty energy efficiency installations. The letter disputes TrustMark's account of when DESNZ was informed of compliance issues, citing DESNZ's own written evidence that it found no records of systemic problems being raised before October 2024. The CEO also corrects inaccuracies in DESNZ's written response regarding consumer guarantee processes.

Key findings

  • TrustMark's oral evidence suggested DESNZ was aware of developing compliance problems from late 2022, but DESNZ's written evidence confirms no departmental records or staff confirmation of systemic issues being raised before October 2024
  • TrustMark identified issues and received complaints from late 2022 onwards but did not formally escalate concerns to DESNZ for 18 months, leaving Certification Bodies with minimal time to investigate
  • DESNZ's written response incorrectly stated consumers must use TrustMark's dispute resolution process first; consumers can contact installers directly and only escalate if the installer fails to respond
  • Protected fund guarantee providers like The IAA typically intervene automatically on failure to rectify, whereas Insurance Backed Guarantee providers operate on insolvency-only basis requiring consumers to pursue FCA Ombudsman claims
  • The letter requests the Committee consider whether clarification or correction of the oral evidence record is required

Tone

Adversarial

Topics

energy-efficiencyconsumer-protectiongovernment-contractscompliance-enforcement

Key actors

Nigel Donohue, Simon Ayers, Sir Geoffrey Clifton-Brown, Installation Assurance Authority Federation, TrustMark, Department for Energy Security and Net Zero, Certification Bodies, The IAA

Notable line

Mr Ayers' oral evidence, knowingly or otherwise, gave the Committee a misleading impression as to the timing and extent of information shared with DESNZ …

Key Quotes

In light of the Department's written submission, it appears that Mr Ayers' oral evidence, knowingly or otherwise, gave the Committee a misleading impression as to the timing and extent of information shared with DESNZ, and therefore as to when the Department could reasonably have been expected to act.
Nigel Donohue · Disputing TrustMark's account of DESNZ's awareness of compliance issues
DESNZ have found no evidence that it was informed of any systemic or material problems relating to non-compliant Solid Wall Insulation installations under ECO4 or GBIS prior to October
DESNZ (Interim Permanent Secretary, as cited) · Department's position on when it became aware of non-compliance issues
Where an installer is still trading, consumers are fully entitled to contact the installer directly in the first instance. If the installer does not respond, or fails to provide a reasonable solution, then the consumer may choose to escalate the matter through TrustMark's dispute resolution process.
Nigel Donohue · Correcting DESNZ's inaccurate statement on consumer guarantee procedures
By contrast, The IAA's market leading guarantee provides cover irrespective of the installer's trading status and is designed to step in to remediate poor workmanship rather than simply offer compensation.
Nigel Donohue · Distinguishing protected fund versus insurance-backed guarantee operations
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Source · parliament.uk record ↗

Letter from the Chief Executive Officer of the Installation Assurance Authority Federation relating to the Committee’s evidence session on 13 November 2025 on Faulty energy efficiency installations, 23 December 2025 | Beyond The Vote | Beyond The Vote