What We’re Learning About Designing Homes That Work — For Comfort, Climate, and the Long Term

Insights from our practice on how thoughtful design can support comfort, reduce impact, and help homes adapt to a changing future.

There is a growing conversation about how we make homes more sustainable, more efficient, and more resilient — but much of it remains technical or hard to interpret. Energy ratings. MJ per square metre. Star targets. It can all feel a bit abstract.

This has led to an increasing focus on energy ratings as a proxy for that conversation. But while they’re a helpful part of the toolkit, they don’t always capture what really matters — or how homes actually feel to live in. Comfort, adaptability, embodied carbon, future climate — these are equally critical, but less often explained.

Through our own practice, we continue to learn what matters most — and where the real opportunities lie. This is a simple sharing of what we are seeing and understanding — to help demystify the conversation, and to support better outcomes for homes and the people who live in them.

Understanding What Energy Ratings Do — And Don’t

Energy rating tools like NatHERS model how much heating and cooling a home is likely to need across a year, based on fixed internal temperature bands. This helps identify where energy demand is highest — and where design improvements like shading, insulation, or orientation could reduce it.

These results are then expressed as a 0–10 star rating. It’s a simple and effective benchmark — useful for checking compliance or comparing different design options. But it’s only ever a model — based on assumptions and simplifications.

NatHERS uses historical climate data (mostly from 1990–2015) and assumes fixed occupancy and behaviour. That means it’s not modelling for a future climate, nor tailored to how a specific household will actually live.

And while it includes options for passive design features — like glazing performance, insulation levels, thermal mass, and even ceiling fans — it can’t account for everything that affects real comfort: air movement, humidity, adaptability, or the dynamic nature of people and place.

Still, as a design tool, it’s valuable. Especially early on, when comparing orientation, layout, and envelope strategies. But it’s critical to remember that it’s one lens — not the whole picture.

Why Chasing One Number Isn’t Enough

At times, pre-defined performance targets can push outcomes in a direction that isn’t necessarily aligned with the original intent. Optimising for a single metric can introduce complexity, cost, or unintended trade-offs — even while trying to do the right thing.

Prioritising energy alone can increase embodied carbon. Prioritising embodied carbon alone can compromise thermal performance or long-term resilience. Prioritising operational efficiency can lead to over-specified systems that reduce flexibility, increase maintenance, or undermine simplicity.

This is the risk of performance becoming a proxy for sustainability — rather than a measure of specific outcomes. It’s also why qualitative design judgement still matters.

We’re not suggesting throwing targets away. We rely on benchmarks to assess and verify. But we also need to ask what it is we’re actually measuring — and whether that reflects the broader environmental, social, and experiential goals we hold.

Our experience points to the value of systems thinking — balancing multiple performance considerations, and understanding how they interact with materials, climate, culture, and comfort. And looking beyond carbon alone to include resource use, material life, and biodiversity impact.

Designing with Sufficiency in Mind

In our 39S House project, we began with the ambition of achieving a 10-star NatHERS rating — seeing it as a way to push performance while reducing energy demand.

We reached a 9.4-star design — but doing so introduced new complexities. Double glazing became necessary, material loads increased, and embodied carbon rose — without delivering significant additional thermal benefit.

We paused. And stepped back to ask what really mattered.

What emerged was a clearer alignment with our values: comfort, durability, clarity, and contextual responsiveness. By rebalancing the design lens, we reduced the star rating to 7.7 — but in doing so, we halved the glazing requirement (using single low-e glass), simplified construction, and reduced both cost and embodied carbon.

It was a better home — not just on paper, but in practice.

Stepping back from this single metric enabled other design opportunities to come forward. One example was the ability to move away from a conventional concrete slab. By adopting a lighter, more permeable ground structure, we were able to reduce embodied carbon, improve on-site water absorption, and help mitigate downstream overland flow — a critical consideration in Brisbane’s flood-prone urban environment. It also future-proofed the home’s thermal behaviour: as subsoil temperatures rise over coming decades, heavy ground-coupled slabs will increasingly risk working against comfort, while a lighter structure supports long-term resilience and indoor comfort.

This is the value of a sufficiency mindset. By rebalancing the design lens, we reinforced outcomes that matter deeply for place and climate — hydrology, resilience, material simplicity — while still achieving strong passive thermal performance.

Sufficiency is not a static target. It is a way of thinking — one shaped by consideration, resourcefulness, and purposefulness. One that allows us to design with clarity and care, creating homes that feel grounded, generous, and enduring.

What Makes a Home Feel Like Home?

For most people, the motivation to build or renovate a home isn’t about performance metrics. It’s about wanting a home that feels good to live in — a place that’s comfortable, safe, and responsive to how you live.

But in the pursuit of sustainability, we can sometimes lose sight of that. We can end up with homes that are well-rated, but underperforming. Spaces that feel complex, over-specified, or not quite suited to the way people actually live.

We see this as a fundamental limitation in the way performance is often framed today. A more thoughtful approach begins with listening — to people as well as place — and responding to context. Understanding that sustainability is broader, more layered, and more enduring than any single metric can express.

Designing with sufficiency helps keep that perspective alive. It encourages refinement, not excess. It respects limits — but also adapts with care. It asks not how much we can achieve, but how little we need to deliver something lasting and meaningful.

That, for us, is the heart of good architecture — and the ongoing challenge of making homes that work.