Putty Passiv

Nestled in the tranquil and sheltered Putty Valley, Putty Passiv is an off-grid camper’s refuge. Occupying Wonnarua and Darkinjung Country, Putty Passiv has been designed to sit within the landscape, blending into its surroundings and positioned away from sightlines from Putty Valley Road. Adhering to the Passivhaus framework, the design of the home reflects a gradual evolution in thinking in response to bushfire resilience and environmental performance. The single storey bushland retreat comprises of two pavilions, with living, kitchen and dining spaces to the north and main entry, bathroom, mudroom/laundry, and bedrooms to the south.

Original schemes positioned the living spaces facing west, but the house was later reorientated to look towards the significant ‘mother’ tree on the site, a large Angophora floribunda, centring the house around the majestic landscape. With solar exposure limited by surrounding trees, the topography and hillside was carefully modelled to achieve optimal winter solar gain, optimising the northern pavilion’s solar access throughout the day, whilst providing adequate shading during the heat of summer.

Achieving Passivhaus certification, the retreat demonstrates rigorous attention to energy efficiency and occupant comfort. Putty Passiv maintains an airtightness of 0.6 ACH, a key metric in reducing energy demand and ensuring thermal stability. Additionally, prefabricated wall, floor and roof panels were manufactured to meet Passivhaus standards, enabling precise control over insulation, thermal bridging, and overall performance.

A unique aspect of this home is that it is one of the first Passivhaus-certified building in Australia to incorporate a fireplace. Traditionally, fireplaces conflict with the airtightness requirements of Passivhaus standards, but here the design was carefully resolved with direct fresh air supply and a certified ultra-low emissions (ULE) unit. The chosen fireplace, a Jotul F162, was deliberately low output to ensure it would not overheat the house, functioning instead as a comforting backup during the winter months rather than a primary heating source. Additionally, two small, highly efficient air-conditioning units (one in each pavilion) can run the entire home independently, ensuring flexibility and resilience in the system design.

Intense bushfires of February 2018 left visible scorch marks and scars across the remaining trees and remnant bushland. In response, Putty Passiv has been designed diligently to ensure the safety of occupants and assets during bushfire events, while also providing for controlled, optional burning of surrounding bushland when appropriate. External façade materiality and fenestration schemes have been designed to provide both excellent interior environmental conditions and maximum protection of the dwelling in the event of a bushfire. A home that is airtight and well-sealed is also highly resistant to the embers and smoke during a bushfire, demonstrating the alignment of Passivhaus principles with bushfire resilience. Putty Passiv has been designed to not simply protect the home against natural forces but accommodate the processes of Country, allowing the home to support human safety and ecological health.