The Flight Of The Bird

By Graham Hepburn

When Johann Bernhardt was seeking inspiration for a sustainable home he was designing on the slopes of the Hunua Ranges, he didn’t have to look far.
“The clients took me to the section and I was looking down at the plains going out to the Manukau Harbour when this big bird appeared and started to float down the slope with its wings spread and that’s when the idea came to me for ‘the flight of the bird’,” he says.
Johann, a Berlin-trained architect, went away to refine his ideas for a home with a wing-shaped roof that would incorporate the passive solar design principles he has championed with Bernhardt Architecture and in his role running the Auckland office of the Building Biology and Ecology Institute.


Johann had been approached by Pam Dormer and Gerry Swift to build the house after Pam had met him at an eco show.
Pam had previously owned a home that used passive solar design so when she and Gerry decided to build a home together, “that was the natural way to go”, says Gerry.
The couple also wanted a home with a high standard of sustainability and resilience on a 1 ha site that enjoys wide views over the plains and the Manukau Harbour. They also stipulated no water and wastewater reticulation, energy efficiency, and a healthy indoor environment – all wrapped into a stylish package.

The home stretches east to west and is low to the south to protect against cold winds but opens up to the north to capture the sun’s energy in its concrete floors, which warm up during the day and release the heat at night. Johann also placed the garage on the southern side of the house to provide a barrier to cold winds although there is a gap between it and the house to allow for cross-ventilation of the home during the warmer summer months. A larger roof overhang on the northern and western sides also helps to keep the sun out and the home cool during summer.
 
In combination with beefed up insulation and double glazing on the east, west and south sides, the indoor temperature can be maintained at a comfortable level throughout winter. Even the expanded polystyrene sheets used as underfloor insulation have been recycled from a building that was being demolished.

“The solar gains are considerable but not like a heater so in order to keep that heat in the house you need better insulation and double glazing,” says Johann.“I always ask my clients after winter if they have started the heater and my aim is that they should hardly ever need it.”

Gerry reports that they occasionally use their high-efficiency woodburner for heat and sometimes so its wetback can help raise the temperature of the hot water system if poor weather has meant the solar panels aren’t doing their work.
Using COLORSTEEL® for the cladding and roofing was an easy choice for Johann.
“It’s low maintenance, looks good, keeps the colour and it’s good for wind and weather,”
says Johann. “I also liked having part of the house in flat materials and to contrast that with three dimensional materials like the corrugated iron.”
Rather than carve out a flat building site, Gerry and Pam decided to build their home into the slope. Not only does this make it easier on the eye, but it also means the home is more sheltered. The master bedroom occupies the lower level, with the rest of the home on the upper level.

Johann also included a central conservatory on the upper level and this has a concrete wall that collects and redistributes heat. This heat can be vented into the house in winter or outside in summer.
Energy efficiency wasn’t Pam and Gerry’s only concern - they also wanted a home that collected its own water and dealt with all its occupants’ waste. Rainwater for drinking and irrigation is stored in in-ground tanks, while wastewater is treated on site. Toilet and kitchen wastewater goes through a worm composting system that treats the water before it joins the “grey water’ from the rest of the house in a siphon tank that slowly releases  into a soakage field planted with flaxes and grasses. The forces of gravity power the process, and the castings produced by the worms in the composting system are used to fertilise the gardens.
Using pine for the decking and environmentally friendly paints were other sustainable choices in a home so striking that Johann used it on the cover of his recently launched book, ‘A Deeper Shade of Green’. He spent a year editing the book, which has contributions from experts in every field relevant to sustainable housing.
Johann, who admits he’s been  “at the fringe struggling hard to get the word out” about sustainable housing, hopes the book will point law-makers, councils, manufacturers, architects and builders down the right path at a time when global warming and soaring energy prices are becoming huge concerns.
“A sustainable home beats a conventional home hands-down in terms of costs during the life cycle of the home,” he says. “Unfortunately, the problem for New Zealand is that people here sell very often and move very often so they tend not to plan for the long term.” 
He says this short-sightedness is one of his major frustrations. “Whenever I talk to people about solar panels the first thing they ask me is what is the payback time but the same people will spend a lot of money on a granite bench trying to keep up with the Joneses but won’t ask about a payback time on that – it’s crazy.
“The comfort of living in a well-designed house should count for a lot more than money.”