From a BGA information sheet:
“Similar in design principle to other hospitals designed by Bertrand Goldberg, each floor of St. Mary’s is arranged into four villages of 14 beds, grouped around a central bed tower support core. Because of the size of each village, it was impossible to create a structural shell; the bed tower floor loads therefore are supported by traditional system of columns arranged radially around a central column located in the middle of each village. The exterior walls of the patient village are constructed of precast concrete, using a traditional rectilinear window since the walls are not structural.”