The six central rooms are placed three to a side, each with a doorway to the central passage and french doors to the verandah. There is a kitchen, a bathroom and two sitting rooms in the rear enclosed verandah. At the front of the house, the southeast room has been extended into the verandah and rebuilt as a chapel, with a Gothic pointed arch opening inserted into the west wall. There are pointed arch ventilating openings to the internal doorways of the two front rooms, and ornamental crosses cut into the front porch panels. The core walls are of exposed frame construction with horizontal chamferboards with curved rebates, fixed to the inside face of vertical studs, with one bracing member in the centre of each wall. The house has pine floors throughout, nailed to joists on doubled bearers and supported on adzed round hardwood stumps; cover strips conceal the central cut along the passageway that is evidence of the house having been moved onto the site. Verandahs have raked ceilings lined in pine, and are enclosed with painted timber louvres. Interior walls and ceilings are lined with painted pine boards, with wall linings to the passage side. The area under the northern verandah has been built in to form a suite of rooms, with maps painted on the walls, illustrating their former function as school rooms. St Mary's Church & Convent was listed on the Queensland Heritage Register on 2 January 1993 having satisfied the following criteria. The place is important in demonstrating the evolution or pattern of Queensland's history. St Mary's Church, erected in 1888 with 1923 additions, is important in demonstrating an aspect of the pattern of Queensland history, namely, the establishment and growth of the Catholic Church in North Queensland. It also retains its s layout and fabric, and is significant as an early, intact residence of substantial proportions in Townsville. It demonstrates part of the pattern and evolution of Queensland history, surviving as important physical evidence of the widespread removal, transportation and re-erection of timber buildings in Queensland in the 19th and early 20th centuries, and more precisely, of the large numbers of buildings removed from Ravenswood and Charters Towers to Townsville in this period. The place is important in demonstrating the principal characteristics of a particular class of cultural places. St Mary's Church remains substantially intact, and is important in demonstrating the principal characteristics of a simple, evolving timber church of the late 19th/early 20th centuries, in Townsville. The place is important because of its aesthetic significance.