Dar-ul-Sukun is run by the Sisters of St Joseph and provides a home for up to 170 mentally handicapped children, almost all of them Muslim. The building is set back from the busy Kashmir Road, for noise reduction and environment control. It is three storeys high, the maximum permissible limit under current building regulations, although structural provision has been made for two to three additional floors. The internal walls are only 2.13 metres high, to allow for cross-ventilation and easy supervision. The structure is of reinforced concrete with concrete block infill walls and 5cm concrete facing tiles.