This historic place was registered under the Historic Places Act 1980. The following text is from the original Building Classification Committee report considered by the NZHPT Board at the time of registration. DESCRIPTION: Otahuna was built in 1895 for Sir Robert Heaton Rhodes (1861-1956) and his initials appear in a pedimented plaster panel inset on the building's exterior north wall. Rhodes was a leading member of one of Canterbury's pioneer families. Born at Purau, Banks Peninsula, Rhodes trained as a lawyer and went on to become MP for Ellesmere from 1899 to 1925. Rhodes married Jessie Cooper Clarke in 1891 and built Otahuna shortly after. He subsequently developed a paternal interest in the nearby village of Tai Tapu. He built the Anglican church in Tai Tapu as a memorial to his wife who died in 1929, and donated the land on which the local library was built. The latter building was paid for by the sale of daffodils from Rhodes' estate. In 1914 Rhodes gave 14 acres of land to the City of Christchurch for the extension of the Summit Road and he is also remembered for his keen interest in gardening.

This historic place was registered under the Historic Places Act 1980. The following text is from the original Building Classification Committee report considered by the NZHPT Board at the time of registration. ARCHITECTURAL DESCRIPTION: Otahuna is a two-and-a half storey wooden residence designed in the Queen Anne style with shingle style overtones. Clad in lapped weatherboards and timber shingles, with a slate roof, the house has three principal elevations which feature an asymmetrical arrangement of different window types and gabled bays. Tall brick chimneys punctuate the picturesque roofline of the building and a special decorative feature of the north elevation is the external chimney breast, rising the full height of the wall, which bears a pedimented plaster panel inset with Rhodes' initials and another giving the year in which Otahuna was erected. Half-timbering and stucco provide further variations in surface texture. The house is approached from the east and the principal rooms on both the ground and first floors are arranged around a two-storey verandah. Between the family rooms in the northern part of the house and the service rooms in the south, the billiard room opens off a verandah which runs perpendicular to the main axis of the house (north-south). A single storey service wing containing the laundry, washhouse, woodshed, meat room, dairy and other ancillary rooms terminates the south end of the building. The most spectacular rooms inside Otahuna are the entrance hall, living room, dining room and billiard room which are in near original condition. Pressed zinc ceiling panels in the hall and dining room, leaded fanlights in geometric patterns, a blue and white silk carpet in the living room, the dining room's original elephant hide chairs and sofa, and the open timber ceiling of the billiard room, are just some of the most notable features of this grandiose building. From the entrance hall the main staircase rises in four flights to a large landing off which seven bedrooms, two bathrooms and a study open, before a change in floor level indicates the move into the servants' wing which contains three more bedrooms and various service rooms. By the back stairs on this floor is a toilet and chamber pot sluice which empties on the ground floor, and above this part of the house are a trunk store, another two bedrooms and the loft. MODIFICATIONS: c.1905 Addition to billiard room - raised section with fireplace at south end. c.1930 West wall, ground floor, living room: two sash windows replaced by a bay window. West wall, master bedroom: oriel window replaced by a balcony. c.1975-80 Kitchen modernisation. Two aluminium windows inserted, section of east wall moved. Original kitchen converted to a family dining room. New kitchen installed in former butler's pantry and servants dining room.