More than 100 schools in England have been told to fully or partially close because they are fitted with a concrete that could suddenly collapse. Reinforced autoclaved aerated concrete (Raac) is a lightweight building material useds since the 1950s up to the mid-1990s, but is now assessed to be at risk of collapse.

More than 100 schools in England have been told to fully or partially close because they are fitted with a concrete that could suddenly collapse. Reinforced autoclaved aerated concrete (Raac) is a lightweight building material useds since the 1950s up to the mid-1990s, but is now assessed to be at risk of collapse.