Nett Zero Box
This house in Alexandra, Central Otago is for clients who had previously enjoyed an Aonui-designed family house in St Bathans. The challenge of a net zero energy home in Central Otago is primarily one of capitalising on the maximum amount of passive solar and photovoltaic harvesting to help maintain thermal comfort throughout the temperature range between 35°C in summer and -10°C in winter.
High levels of insulation were achieved using SIPS panel construction to ensure thermal performance. The roof is angled at 32° towards north to maximise solar panel efficiency and aim for a net positive annual power generation. The ever-present and common risk of summer overheating in passive solar houses is avoided by strategically placed high level south wall windows that expedite warm air expulsion by stack ventilation.
