What is RAAC?

Reinforced Autoclaved Aerated Concrete (RAAC) is a lightweight, precast concrete material used extensively in the UK from the 1950s to the 1990s. Found in schools, hospitals, and other public buildings, it was originally praised for being cost-effective and easy to install. However, it has since become recognised as a material that poses serious structural risks if not properly maintained or replaced.

Key Issues with RAAC

RAAC presents several critical issues that building owners and facilities managers must be aware of:

Structural Weakness -  RAAC has a significantly lower strength compared to traditional concrete. Over time, it can become brittle and prone to sudden failure—often without visible warning.
Moisture Absorption -  RAAC is highly porous and absorbs moisture easily. This leads to accelerated degradation, especially in roofs and ceilings where water ingress is common.
Corrosion of Reinforcement  – The embedded steel reinforcement within RAAC can corrode over time, weakening the bond with the concrete and reducing the overall load-bearing capacity.
Limited Lifespan - RAAC has a shorter design life (around 30 years), and many installations are now well beyond their intended service period.
Sudden Collapse Risk - Unlike traditional concrete, RAAC structures may fail with little to no warning signs, creating urgent safety concerns.

These vulnerabilities make it essential to identify RAAC in buildings, assess its condition, and take action before failures occur.

(Image by freepik)

Why It's Important to Act

The presence of Reinforced Autoclaved Aerated Concrete (RAAC) in buildings presents a significant and growing concern for property owners, facilities managers, and duty holders. Left unaddressed, RAAC can pose serious structural, financial, legal, and safety risks. It is not enough to simply be aware of the issue—decisive action is required. The following key points highlight the critical consequences of failing to properly assess and remediate RAAC-related issues, underscoring why proactive management is both a legal responsibility and a moral imperative.

Unexpected closures and loss of access to key services

RAAC has a known tendency to deteriorate over time, particularly when exposed to moisture or structural stress. If these issues go unaddressed:

Buildings may need to be suddenly closed when structural integrity is deemed compromised, often with little warning.
This can disrupt essential services—such as schools, hospitals, government buildings, or transport hubs—leading to major inconvenience for the public.
These closures often occur with little to no contingency planning, intensifying the operational impact.

Expensive emergency repairs and downtime

If RAAC problems are not proactively identified and resolved:

Structural failures or urgent safety concerns may require immediate and costly emergency repairs.
Emergency work often involves premium rates for materials, labor, and rapid mobilization.
The lack of planning typically results in longer downtime, which can affect business continuity or public services.
It also limits opportunities to explore cost-effective remediation options that could have been used with earlier intervention.

Increased safety risks for building occupants

RAAC is a lightweight material that loses strength over time and can collapse without warning, especially if moisture penetration has weakened it:

Failing to address its condition puts occupants—whether employees, students, patients, or the public—at serious risk of injury or death.
Falling ceiling panels or partial roof collapses are documented risks when RAAC fails structurally.
This creates a duty of care breach and reflects poor building management, which may have reputational consequences as well.

Potential legal and regulatory consequences

Building owners and duty holders are legally obligated to ensure the safety of their premises. Ignoring RAAC-related risks can lead to:

Legal action, including civil lawsuits from injured parties or those impacted by closures.
Fines or enforcement from health and safety regulators such as the HSE (Health and Safety Executive in the UK).
Insurance complications, as insurers may reject claims or increase premiums if RAAC risks were known and ignored.
Possible criminal liability in extreme cases where negligence leads to harm or death.

Our Work at Hinchingbrooke Hospital

We have been proud to deliver essential RAAC remediation and structural upgrades at Hinchingbrooke Hospital, playing a key role in protecting patient safety and ensuring uninterrupted healthcare services.
This large-scale project involved targeted work across several critical areas of the hospital, including the:

Maternity Wards
Pharmacy Department
Pathology Laboratories

Each of these environments demanded a unique and highly sensitive approach—not just to the construction work itself, but to the hospital’s daily operations and the wellbeing of patients and staff.

Working in a Live Hospital Environment

Delivering building works within an operational hospital is a significant challenge. At Hinchingbrooke, our teams worked seamlessly alongside clinical staff to ensure that disruption was kept to an absolute minimum. This involved:

Detailed phasing of works to allow hospital services to continue uninterrupted.
Noise and vibration management protocols to prevent disturbance during medical procedures or rest periods.
24/7 coordination with hospital departments to ensure emergency routes, equipment access, and staffing zones remained fully functional.

Our staff were specially trained in hospital-site conduct, infection control, and safeguarding protocols to maintain a safe environment at all times.

Patient Privacy and Safety

We understand that healthcare settings demand the highest levels of discretion and respect. Throughout the project, we implemented strict privacy protections, including:

Physical barriers and soundproof partitions to separate work zones from patient areas
Clear signage and safety wayfinding for staff and visitors
Regular briefings with hospital staff to align on patient movement and access timing

Our focus on sensitivity and professionalism ensured patients, families, and frontline workers were never put at risk or discomfort during construction.

Adapting to Complex Access Requirements

Hospital infrastructure is complex, with limited access points and critical areas that cannot be obstructed. We developed custom access strategies to overcome these constraints, including:

Off-hours deliveries and modular lifting plans to minimise disruption
Use of temporary corridors and scaffolding to maintain safe passage
Close collaboration with estates teams to understand essential utility lines and systems

Our experience in healthcare environments enabled us to adapt quickly and maintain compliance with NHS standards throughout.

Developing Quality Assurance Procedures

We believe that quality in construction is not just about the finished product—but how it performs safely and reliably over time. At Hinchingbrooke Hospital, we created bespoke quality assurance procedures to suit both the technical requirements of RAAC remediation and the operational sensitivity of a hospital setting.

These included:

Detailed pre-installation inspections and photographic records
Regular progress audits and site reviews with NHS Trust stakeholders
Independent testing and verification of all structural elements
Digital handover packs including structural drawings, compliance certificates, and maintenance guidance

Our commitment to transparency, accountability, and excellence helped build trust with hospital leadership and ensured long-term peace of mind.

Your Trusted Partner for RAAC Solutions in Critical Environments

If you suspect RAAC may be present in your facility, proactive assessment and timely remediation are essential to protect the safety, compliance, and continuity of your operations.

We specialise in delivering safe, efficient, and high-quality RAAC solutions—particularly in live, sensitive environments such as hospitals, schools, and public sector buildings. Our work at Hinchingbrooke Hospital is a testament to our ability to operate with precision, care, and minimal disruption, even in the most complex settings.
We offer:

Thorough surveys and risk assessments
Cost-effective RAAC removal and structural replacement
Full project management from initial planning through to completion
Operational sensitivity – working around live services, safeguarding patient privacy, and maintaining day-to-day functionality

Whether you’re planning scheduled upgrades or facing urgent RAAC concerns, we bring the technical expertise, quality assurance processes, and trusted site conduct needed to deliver results—safely and reliably.

Contact us today to arrange a consultation and discover how we can support your buildings, your people, and the vital services you provide.