The building was built originally circa 1684, of 3 storey height stone construction and served by one northeast staircase accessing the viewing balcony and Organ, there are no lift facilities.During the buildings' life it has remained as originally constructed, a fire exit/escape route has been added from the balcony into the West Theatre offices at 2nd floor level.The main hall forms part of the overall structure which includes the East and West Theatre office blocks all constructed around the same era.