Understanding NatHERS Star Ratings: More Than Just Numbers

What the stars actually mean...

When you see a NatHERS star rating on a home, it’s not just a badge of compliance. It’s a snapshot of how comfortable, efficient, and resilient that home will be across the seasons.

A 1 Star home struggles. It’s hot in summer, freezing in winter, and expensive to run.

A 3–4 Star home performs a little better but still leaks energy through poor insulation, orientation, or glazing.

A 6 Star home is almost there, but the home wont be comfortable year round.

Homes that reach 7 Stars and above are in a different league. They’re naturally more stable in temperature, cheaper to operate, and far kinder to the environment.

Each extra star represents smarter design choices that reduce the need for artificial heating and cooling.

What impacts your rating

NatHERS software measures how your home design performs thermally. It considers:

• Orientation: How your home captures sunlight and manages heat.

• Glazing: The type, size, and placement of windows.

• Insulation: How effectively the building envelope retains warmth or coolness.

• Shading: Whether eaves, blinds, or landscaping help manage summer heat.

• Construction materials: How walls, floors, and roofs store and release energy.

All these elements interact. A small design tweak early in planning can lift your star rating, improve comfort, and cut lifetime costs.

Why it matters

The star system doesn’t just serve regulators, it serves homeowners too.A higher NatHERS rating means:

• Lower power bills

• Less reliance on air conditioning

• Greater comfort all year round

• A smaller environmental footprint

And if you’re selling or renting, it also adds long-term value. As energy efficiency becomes a key selling point, better-rated homes stand out.

It’s not just about stars, it’s about how your home feels

A compliant 6 Star home might tick the box, but a well-designed 7 or 8 Star home feels different. It’s balanced, breathable, and naturally comfortable, the kind of space you notice the moment you walk in.

At Studio Terra, we help homeowners, builders, and designers understand how their plans perform before construction begins. Using accredited software and a practical design approach, we show you exactly where your design can improve and how to lift your rating without compromising aesthetics or budget.

See how your plans perform

If you’re planning, building, or reviewing a project and want clarity around your NatHERS rating, we can help.