Following an alarming revelation, Education Secretary Gillian Keegan disclosed a concerning issue that has sent shockwaves through the education sector in England. On Monday 4th Septemeber 2023, over 100 schools, colleges, and nurseries were ordered to close due to a material known as RAAC, short for reinforced autoclaved aerated concrete, found in their buildings. This lightweight building material, once considered a cost-effective alternative to standard concrete, has now become a cause for alarm due to its inherent unreliability.
RAAC, with its aerated, bubbly texture, was favoured for its quick production and ease of installation, especially in flat roofing, floors, and walls. However, its cost-efficiency came at a significant trade-off. Unlike traditional concrete, RAAC has a much shorter lifespan, typically around 30 years. Moreover, its vulnerability to moisture is a glaring weakness, as water can infiltrate the structure through the air bubbles, causing structural instability and potential collapse.
The question arises: why was RAAC used in the first place? The answer lies in its ability to offer thermal insulation and its weighless nature, which expedited construction processes. But as we are now painfully aware, these advantages have come back to haunt us.
How is RAAC Manufactured?
RAAC differs structurally from traditional concrete due to its unique production process. Raw materials are mixed and poured into molds, after which a high-pressure autoclaving process, involving exposure to steam and pressure, is employed to create RAAC. This process results in the formation of air bubbles within the structure, contributing to its lightweight properties.
RAAC found its heyday between the 1950s and 1990s when it was actively used to construct various buildings across Britain. However, concerns about its shortcomings were not a recent development. As far back as the 1960s, RAAC’s differences from traditional concrete were documented. In the 1980s, a report by the Institution for Structural Engineers highlighted that short-term exposure to moisture could reduce the material’s strength by approximately 13%, while long-term exposure to air pollution could diminish it by as much as 40%.
In 1996, a government-funded report by the Building Research Establishment revealed cracks in RAAC panels in housing developments and structural issues in panels installed in schools. In response, a Labour government in 2003 initiated a plan to refurbish all of England’s secondary schools. However, this project was dropped by the Tories in 2010 due to perceived cost ineffectiveness.
The recent crisis has prompted urgent calls for an audit of RAAC’s usage in other public buildings, including hospitals. The Labour Party is leading the charge in demanding clarity on the extent of the issue, while investigations have even been launched into whether RAAC was employed in the construction of the iconic Houses of Parliament.
In the midst of this crisis, it’s evident that a shift towards more robust and durable building materials is crucial. The discovery of RAAC’s shortcomings serves as a stark reminder of the importance of prioritising safety and longevity in construction. Modular solutions and sustainable building materials should take center stage in the quest for safer and more resilient infrastructure.
Find the list of schools released in the report by the Government here.
Why Modular Construction is The Ideal Solution for Schools
Modular construction, also known as off-site construction, offers a range of advantages that are particularly well-suited for the challenges faced by the education sector today.
Speed and Efficiency: Modular buildings are known for rapid construction timelines. Modules, which are pre-fabricated in controlled factory environments, can be quickly assembled on-site. This means that schools can be constructed or expanded in a fraction of the time compared to traditional construction methods. In the context of the RAAC crisis, speed is of the essence in ensuring that affected schools are rebuilt or repaired promptly.
Quality Control: Modular construction involves the manufacturing of building components in a factory setting, where quality control measures are stringent. This significantly reduces the risk of defects and structural issues, ensuring that the final structure is built to the highest standards. Given the concerns about RAAC’s durability and its susceptibility to moisture, the reliability of modular construction is paramount.
Safety and Compliance: With modular construction, compliance with safety regulations and building codes is closely monitored throughout the manufacturing process. For portable cabins in Schools especially, this guarantees that the final structure meets all necessary safety standards. In contrast, the discovery of RAAC in schools highlights the importance of stringent quality checks and compliance in construction, which modular construction inherently provides.
Sustainability: Prefabrication often involves the use of sustainable materials and practices. This aligns with the growing emphasis on eco-friendly and energy-efficient school buildings. In an era of increasing environmental awareness, choosing sustainable construction methods is not just responsible but also cost-effective in the long run.
Flexibility and Adaptability: Modular classrooms are designed with flexibility in mind. They can be easily expanded, reconfigured, or relocated to accommodate changing educational needs. This adaptability is crucial as it allows schools to respond to fluctuations in student enrollment and evolving teaching methods.
Reduced Disruption: Traditional construction can be highly disruptive to school operations. Modular construction minimises on-site disruption, as much of the work is completed off-site. This is especially relevant when considering the impact of school closures due to structural concerns like RAAC.
Cost-Effectiveness: Modular construction can offer cost savings in terms of reduced labour and construction time. Funds allocated for repairs and rebuilding in the aftermath of the RAAC crisis could be used more efficiently through modular solutions.
Final Thoughts about RAAC in Schools
In essence, the RAAC crisis serves as a stark reminder of the paramount importance of prioritising safety and longevity in construction. It is a call to action for the education sector and beyond to embrace sustainable and reliable building materials and methods to ensure the safety and well-being of students, staff, and the community as a whole.
In light of these revelations, it is clear that a shift towards more robust and durable building materials is imperative. Modular construction, also known as off-site construction, emerges as an ideal solution for schools and other public buildings. Its advantages, including speed and efficiency, quality control, safety and compliance, sustainability, flexibility, reduced disruption, and cost-effectiveness, make it well-suited to address the challenges faced by the education sector in the wake of the RAAC crisis.
Cotaplan – Offering RAAC Alternatives via Modular Construction
If you’re interested in learning more about Cotaplan’s modular building solutions or discussing how we can address the challenges posed by the RAAC crisis, you can contact us here
Mark Fielding
Freephone: 0800 7999 049
Email: info@cotaplan.co.uk