Trends New Zealand Volume 34 No 5 | Page 44

Above: Just inside the entrance, the stairs have a dramatic sculptural quality. Each 160kg concrete tread is post-tensioned into the concrete wall and cantilevers out to give a floating effect – the wire balustrading plays no structural part in the design. Facing page,top: Kitchen, living and two dining areas form one open-plan space, with large glass panel doors opening up to provide a seamless transition between inside and outside. search | save | share at The 38cm-thick walls, with vapour bar- rier insulation, provide another concrete benefit – acting as a heat sink and reducing the need for artificial heating and cooling For the structural column at the front door, Cheng used a third technique. Con- crete was poured on site into a polyester tube, which was then pinched at various points to create a smooth organic shape. The second storey of the main house is clad in contrasting reclaimed redwood that had been felled over 100 years ago. It’s topped by a butterfly roof concealing the photovoltaic cells covering 60 per cent of its surface. The roof’s angles, pitches and pleats collect rainwater, allowing for potential water tank storage. But rainwater is also channelled to form water features and to interact with some of the concrete walls to create ever-changing art installations. So, at the front of the house, a copper pipe extends over the walkway, spilling out a stream of water from the garage roof during rain showers. Meanwhile, small pumps also direct