The long, bar-shaped house, strategically placed between two river red gum trees, spans the creek. Four small concrete piers, two on either side of the creek, anchor two steel trusses, which form the primary structure. Between the trusses is a concrete floor slab on steel decking with a layer of rigid insulation. Walls and roofing are made of plantation pine, and the exterior is clad with precoated steel panels.

Pressed steel louvers on the north side, ceiling fans, and operable windows facilitate ventilation and shading, omitting the need for air-conditioning. In wintertime, the low sun shines through the double-glazed floor-to-ceiling windows, warming the black concrete floor slab. Additional heating comes from a wood combustion heater. Photovoltaic cells on the roof of the garage supply all electricity and feed whatever is not needed back into the grid.

Water is collected from the roof for use inside the house, and wastewater is pumped some 300 feet from the creek and dispersed underground. “Minimizing impact on the site, creating an efficient structural system, and ensuring that the area of the house was kept to a useable minimum were key elements of the design,” says Pritchard. “The biggest challenge was to create a unique, steel-framed, engineered home at a price comparable with standard houses.”

It’s not just Pritchard’s clients who agree that the house accomplishes its goals—it recently won a residential design award from the Australian Institute of Architects (South Australian Chapter). But for the clients, it’s “that feeling of living in the treetops” that really makes the house exciting. “They say they’re able to view a variety of bird species nesting in the adjacent trees—at eye level—from inside the house,” says Pritchard. “The owners take great pride in the revegetation of the site. They have left city life to fulfill their dream.”