
More than 100 schools, nurseries and colleges in England have been told by the government to close classrooms and other buildings that contain aerated concrete that is prone to collapse.
But what is aerated concrete, and why is it such a risk?

More than 100 schools, nurseries and colleges in England have been told by the government to close classrooms and other buildings that contain aerated concrete that is prone to collapse.
But what is aerated concrete, and why is it such a risk?