Nature gives form, function
HAVING lived overseas for 13 years, the owners of this rammed earth home decided to move back to New Zealand to be close to family.
The location is a rugged narrow terrace at the foot of the Criffel Range near Wanaka.
Subdivided from a farm below, the site overlooks the rural land and distant mountains surrounding Wanaka and had a 15mby30m building platform orientated to the north.
The owners had seen rammed earth used before by Assembly Architects in Wanaka and liked it for its natural qualities and local character.
Their brief was for a relaxed family home where their children remained close, with the ability to work from home and to have guests to stay.
Having been apartment dwellers in Singapore, large bedrooms were not needed but they did want a generous living space well connected to the outdoors. The guest bedroom would double as a reading and yoga space.
Rammed earth walls were used primarily in the living spaces and the perimeter walls of the home. Concrete footings were left exposed and vertical concrete elements were used as dividers — for example, between the lounge and the snug, as a bedhead, and against the kitchen bench.
Tucked behind the corten steel entry door is the study.
The living rooms and all the bedrooms are sited along the northern length of the building platform, capturing the sun and panoramic view.
The centrally placed living room opens on to a patio at the northern terrace edge and into a courtyard on the south. The courtyard provides an escape from the intense northern and western sun and captures views of the rugged terrain above the property.
Monopitched profiled metal roofs were proposed to counter the consent requirement for a gable roof and present a lower building profile. These are flashed in a band of corten steel. Ceilings are lined in New Zealand southern beech, with macrocarpa soffits.
The home uses local materials as much as possible, the most obvious being the earth sourced from Cardrona Valley.
Because the house is sited for maximum northern exposure, the sun charges the 450mm thermal mass walls and exposed concrete floors like a battery. An electric heat pump supports the heating when required; the home is wired to have solar panels and batteries installed when these become more affordable.
Eaves have been designed to prevent high summer sun getting in but allow low winter sun to enter. The home has an even temperature and winter power bills are not extreme.