Examine the emerging fire risks associated with first-generation External Wall Insulation (EWI) systems installed 10-15 years ago. Learn the signs of degradation that can compromise fire performance.. The Silent Threat: Degradation of Early EWI Systems The UK has seen a significant drive towards energy efficiency, with External Wall Insulation (EWI) playing a crucial role in retrofitting existing buildings. However, a growing concern among fire safety experts in late 2026 centres on the fire performance of first generation EWI systems installed approximately 10 15 years ago. While these systems met the regulatory requirements of their time, ongoing observations suggest that the degradation of these materials over a decade or more is beginning to compromise their original fire resistance. This article explores the emerging risks associated with shrinkage, cracking, and sealant failure, which can fundamentally alter a building's fire safety profile. The longevity of these systems, initially championed for their thermal benefits, is now being scrutinised through a fire safety lens, particularly in light of recent, albeit small, incidents highlighting vulnerabilities that were not apparent at the time of installation. An Evolving Landscape: Regulations and Realities The regulatory landscape surrounding building safety, particularly concerning external walls, has undergone significant transformation. The Building Safety Act 2022 (BSA 2022) has introduced a new era of accountability, placing greater emphasis on the safety of higher risk buildings throughout their lifecycle. While earlier EWI installations predated some of these stringent requirements, the BSA 2022's provisions for assessing and managing building safety risks, and the duties of Accountable Persons, necessitate a re evaluation of these legacy systems. Furthermore, the Regulatory Reform (Fire Safety) Order 2005 (RRO 2005) continues to place a clear duty on Responsible Persons to ensure the safety of occupants from fire. The degradation of EWI systems directly impacts a building's fire risk assessment and can elevate the potential for fire spread, directly challenging the assumptions made under the RRO 2005. The Triple Threat: Shrinkage, Cracking, and Sealant Failure The primary concerns with ageing EWI systems stem from three interconnected issues: shrinkage, cracking, and sealant failure. Shrinkage: Over time, thermal cycling and material ageing can cause EWI boards to shrink, creating gaps between panels. These gaps can act as pathways for fire and smoke, bypassing fire breaks and accelerating vertical fire spread. Cracking: Mechanical impact, building movement, and environmental stresses can lead to cracking in the render or outer layers of the EWI. These cracks can expose combustible insulation materials underneath, making them more vulnerable to ignition and fire propagation. Sealant Failure: Sealants, crucial for maintaining the integrity of firestopping around openings and at interfaces, can degrade and fail. This compromise creates unsealed pathways for fire and smoke penetration, undermining the compartmentation strategy and dramatically reducing the effectiveness of fire resisting barriers. The cumulative effect of these issues is a significant reduction in the fire performance originally designed into the system. Beyond the Facade: Impact on Fire Spread and Occupant Safety The deterioration of EWI systems has serious implications for fire spread and, consequently, occupant safety. The Approved Document B (ADB) of the Building Regulations outlines requirements for external fire spread. Aged EWI systems with compromised integrity may no longer meet the performance criteria assumed during their initial installation, potentially allowing fire to spread rapidly across external facades. This contravenes the fundamental principles of fire safety, which aim to limit the rate and extent of fire growth. The increased risk of external fire spread means that escape routes could be compromised more quickly, and the time available for evacuation reduced. Fire and Rescue Services' operational tactics may also be impacted due to unpredictable fire behaviour within these compromised systems, posing additional risks to both occupants and emergency responders. Early Detection: Recognising the Warning Signs Identifying degradation in early EWI systems requires careful inspection beyond superficial visual checks. Responsible Persons and their appointed competent persons should look for: Visible cracking or crazing in the render, especially around openings and corners. Delamination or bubbling of the render surface. Gaps appearing between EWI panels or at junctions with other building elements. Compromised or missing sealant around windows, doors, and service penetrations. Discolouration or staining that could indicate water ingress and subsequent material degradation. Evidence of impact damage or repairs that may have compromised the system's integrity. These