 In 1911 Hamilton Academy's 'prep' (junior) school relocated to its new, separate smaller building behind the main edifice, before completion, in 1913, of the new senior school building in the French Renaissance style and of red freestone from Corncockle Quarry in Dumfriesshire.The main building, with separate entrances for girls and boys, was arranged over three storeys, with additional basements, providing accommodation for rector's office, board room, offices, classrooms, six laboratories, workshops, art rooms and gymnasia.Of particular note were the Central Hall, the large lecture hall (seating 200, gallery-style and communicating with the laboratories) and library, with reading rooms for girls and boys respectively.