An ambitious brief combines with an unassuming site to create an elegantly sustainable Brisbane home.
As with many successful creative endeavours, Project Zero had to overcome a series of challenges. The story begins with a couple seeking to renovate an existing, inner-city Brisbane Old Queenslander to accommodate their young family, meanwhile aiming for a high degree of energy efficiency (the target being zero energy consumption, hence the name). It quickly became clear that despite their romantic reputation, the desired house typology was both prohibitively expensive, and poorly equipped for energy efficient design.
Undaunted, the clients referred to their architect, BVN principal Brian Donovan, to suggest feasible alternatives, and before long settled on the less glamorous, but more affordable and versatile option of a timber home on a wide block of land in Brisbane’s suburbs.
As Donovan recalls, “The initial response was to include re-use of existing building stock in the scheme. Thus, a north falling site with an existing 1950s hardwood framed house was identified to adapt and extend.” Between the timber floors and walls and robust structure, these houses provide a high-quality foundation over which fresh designs can be laid.
The chosen property had the further advantage of a north-facing aspect and slight elevation compared to its surroundings, promoting passive cooling. The generous plot size of 800sqm gave the architect abundant room to manoeuvre, especially with regards to introducing outdoor spaces: as Donovan comments, “The north facing site in a suburban setting determined a courtyard configuration with landscape central to the composition of indoor and outdoor spaces.” Accordingly, the existing structure – a rectangle sitting in the middle of its plot – was moved and expanded to create an L-shape abutting its southwest corner, embracing a verdant and protected outdoor living area.
The addition to the existing structure comprises living, dining, kitchen and study areas, sheltered under a sawtooth roof clad in solar panels. The courtyard includes a covered fireplace, a pool, an encircling timber trellis entwined with vines, a veggie garden, chook house, compost/worm farm and extensive native planting.
As with any project pursuing energy efficiency, materiality was a central concern. As Donovan explains, “Building fabric mass was identified as essential to support the intent for low energy use – thus recycled bricks became the primary material for the extension.”
Indeed, the creative and intelligent use of brickwork is a defining characteristic of Project Zero, with mottled recycled brick flooring bricks serving to blur the boundary between internal and external spaces and acting as a textured offset to minimal concrete and render finishes throughout the home. Brickwork is translated into a plethora of functions, serving, as Donovan points out, “as walls, floors, plinths and landscape edges, to provide a sense of continuous materiality from outdoors to the interior.”
The bricks were sourced from the nearby Austral Bricks Rochedale factory and had originally been used for an underfired kiln in the 1960s, which was then demolished. Fittingly, the inevitable inconsistency in colour caused by their exposure their high temperature setting gave them the aesthetic vibrancy that animates surfaces at Project Zero, and they were carefully laid so as to ensure the most compelling visual impact, and reduce the number of cuts required.
While the use of recycled bricks dramatically lowered the embodied energy of the new build, their configuration also contributes to the home’s ongoing energy efficiency. In particular, double-cavity walls, coupled with bricks’ thermal mass, give the structure substantial insulation. This is further supported by glazing on doors and windows, which allows the home to effortlessly open onto its outdoors or preserve its cool as required.
By combining a series of simple yet effective energy saving measures, Project Zero demonstrates that sustainable design is just as much about using existing materials and techniques intelligently as it is about innovation. In so doing, it is an inspiring example of how much of our built environment can be converted to be more energy efficient, without either needing to compromise on aesthetics, or start from zero.
The go to magazine for architects!