While Reinforced Autoclaved Aerated Concrete (RAAC) has gained recognition for its sustainability and energy efficiency, it is essential to consider potential drawbacks when evaluating its suitability for school construction. In this blog, we will explore some concerns associated with RAAC in educational settings.
What is RAAC?
RAAC, or reinforced autoclaved aerated concrete, is a lightweight material that was commonly used in construction between the 1950s and 1990s. It served as an alternative to traditional concrete, offering cost and time-saving benefits. RAAC is characterized by its aerated or “bubbly” texture, like an Aero chocolate bar. However, it has a shorter lifespan of around 30 years and is less durable compared to standard concrete.
Risks and Issues:
The structural behaviour of RAAC differs significantly from traditional concrete, making it weaker and more susceptible to failure when exposed to moisture. The presence of bubbles in the material allows water to enter, leading to decay, rust, and weakening of any reinforcing rebar. To mitigate these risks, RAAC is often coated with other materials, such as bitumen on roofing panels. However, these coatings can also degrade over time.
The risks associated with RAAC were first identified as early as 1961 when the material was introduced in Britain. Reports highlighted the differences between RAAC and traditional concrete, emphasizing the material’s vulnerability to moisture and polluted air. In the 1980s and 1990s, roof collapses in buildings constructed with RAAC led to demolitions, further raising concerns about its safety.
Mitigation Efforts:
The government has been aware of the potential risks of RAAC since 1994 and has been monitoring the condition of public sector buildings containing the material since 2018. New guidance on managing RAAC was issued in 2021 and 2022, and a questionnaire was sent to responsible bodies to gather information on the use of RAAC in schools across the country.
However, the lack of proper inspection and maintenance of older buildings, including those constructed with RAAC, has been a significant challenge. Schools have faced difficulties due to limited resources and untrained personnel responsible for structural engineering.
Recent incidents, including the collapse of a previously considered low-risk RAAC beam, have prompted the labelling of schools with RAAC as potentially dangerous. As a result, these schools have been closed or partially closed at short notice to ensure the safety of students and staff.
The government invested over £15 billion since 2015 to keep schools in good working order, including £1.8 billion committed for 2023-24.
Conclusion:
RAAC, a lightweight alternative to traditional concrete, poses significant risks due to its vulnerability to moisture and structural weaknesses. The government has taken steps to address these risks, but the lack of proper inspection and maintenance of buildings constructed with RAAC remains a concern. It is crucial to prioritize the safety of individuals by thoroughly assessing and managing the risks associated with RAAC in existing structures.
The government invested over £15 billion since 2015 to keep schools in good working order, including £1.8 billion committed for 2023-24.
Kee Systems supplies the Education Sector for over 40 years
Kee Systems, as a provider of safety solutions and expertise, can play a crucial role in addressing safety issues in schools. Here some potential actions Kee Systems can take:
Free Surveys: Kee Systems offers surveys free of charge, to provide detailed safety recommendations designed to keep people safe.
Safety Equipment Installation: Kee Systems specializes in safety solutions, including guardrails, handrails, and barriers. Whether it’s rooftop edge protection, stair railings at a University entrance, or barriers in the School drop-off zone, our solutions serve to protect students, parents, staff and onsite maintenance contract workers alike.
We understand precisely what is needed to ensure Nurseries, Schools, Colleges and Universities are safe and fully compliant.
