Our response to a national design challenge looked deeply into the health, comfort and carbon implications of single family homes in Australia.
This project isn’t like any of the others featured on our website. It’s actually 24 different iterations of the same single-family home design, tuned for different climates and conditions in each of Australia’s state capitals and designed to deliberately varying levels of performance and comfort.
A huge team of experts contributed to the research, which was spearheaded by Talina Edwards and Andy Marlow of Envirotecture and Luc Plowman of Detail Green. The project was our entry to the Design Matters National True Zero Carbon Challenge competition in 2022 and our Brisbane iteration won the Queensland award.
Our entry went above and beyond the competition brief. Envirotecture architects are thoroughly versed in NatHERS but prefer to use PHPP, the Passivhaus Planning Package software used by Passivhaus designers. Instead of preparing a single design, we entered a matrix of four variations in six locations. This vividly showed the interactions between energy efficiency, occupant health and comfort and carbon emissions.
We wanted to make clear the conversation Australia needs to be having about what we prioritise in our housing. Off-setting an inefficient design by increasing solar energy generation is not a sustainable or desirable way to reach true net zero. Efficiency first! Our research showed that a high NatHERS rating is no guarantee of a comfortable, healthy home and that its Whole of Home tool consistently under-predicts ongoing energy use. [Read more about this here.]
Our design
We dubbed our design the “Little Pot of Gold”. It has three bedrooms, a study (or fourth bedroom), a spacious open plan kitchen/dining room/lounge, excellent storage and great connection to the outdoors. It has two bathrooms in a novel configuration that provides a great deal of flexibility. All this is achieved in 120m2, half the floor area of typical new Australian homes!
We carefully considered how to create a design that was flexible, that would be a welcoming and well-functioning place to live for all kinds of people: families with small children, adults living with elderly parents, or groups of flatmates or best friends living together at different life stages.
Bedrooms have built-in robes plus window seats facing north, creating a warm and sunny spot to lounge in winter that is shaded from hot summer sun. The open-plan living area at the rear of the house has direct access to the deck and back garden. A built-in seat for the dining table offers storage beneath and creates another inviting space connected to the outdoors.
The family bathroom is fully wheelchair accessible without looking like an institutional facility. It includes a bath, separate shower and toilet, with a second toilet in its own room. A second shower is accessed via the laundry. This was carefully considered to reduce the queue for bathroom facilities during busy mornings. Not including an ensuite would be seen by some as a bold move; we wish it wasn’t controversial. We have spread out two bathrooms in a way that provides maximum flexibility for all different kinds of living arrangements.
A compact home feels much larger thanks to multiple outdoor living spaces. A front verandah offers a welcome connection to the neighbourhood, increasing safety and social cohesion. The rear deck is accessed from the kitchen and the carport structure at the front offers lots of flexibility. It could shelter and charge an electric vehicle, or store e-bikes and pushbikes. Or if the occupants are more likely to use public transport or car share schemes, this space can be used as a workshop, outdoor-living area, potting shed or greenhouse.
What we did
The four iterations were as follows. One was optimised to get the best score using NatHERS (National Home Energy Rating System, an Australian initiative). Three more iterations were modelled in accordance with the international Passivhaus standard, which focuses in part on radically reducing operational carbon emissions. The Passivhaus options specified different types of construction material to vary the amount of embodied carbon emissions associated with the design. (Some people call this upfront carbon: it’s the CO2 released during the entire lifecycle of a building, from raw material extraction to demolition and disposal, encompassing all stages of the materials' journey.)
The full designs, details and data can be found on the Pot of Gold website here.
"We wanted to make clear the conversation Australia needs to be having about what we prioritise in our housing. Off-setting an inefficient design by increasing solar energy generation is not a sustainable or desirable way to reach true net zero. Efficiency first!"
Awards
