7 Star Energy Rating: What It Means & How to build for it
8 September 2026
If you are planning to build a new home or undertake a major residential project, you’ve likely heard about the 7 star energy rating. Transitioning from the old 6 star standard, the 7 star minimum energy requirement under the National Construction Code (NCC) and integrated into schemes like New South Wales' BASIX represents a major shift in Australian residential construction.
Far more than just a box to tick for council approval, a 7 star energy rating changes how homes are designed, oriented, and insulated to guarantee year-round thermal comfort and lower utility bills.
What is a 7 Star Energy Rating?
A 7 star rating is measured using the Nationwide House Energy Rating Scheme (NatHERS), which ranks a home's thermal shell on a scale from 0 to 10 stars.
The Building Envelope:
NatHERS software evaluates how well the "container" of your home—its floors, walls, roof, windows, and orientation resists outside temperatures.
The Performance Leap:
Moving from 6 to 7 stars means a home’s heating and cooling energy load is reduced by roughly 25%. The Whole of Home Budget: Alongside the 7 star thermal shell, regulations now feature a Whole of Home energy budget (typically scored out of 100), which evaluates the efficiency of fixed appliances like hot water systems, air conditioning, lighting, and solar generation.
Key Strategies to Achieve 7 Stars
Reaching 7 stars requires intentional choices early in the design phase. Relying on standard, off-the-shelf plans without adjustments often falls short. To secure compliance smoothly, focus on these four core pillars:
1. Smart Orientation
The cheapest energy is the energy you never have to use.
North-Facing Living: Aligning living areas, kitchens, and primary bedrooms toward the north allows low winter sun to naturally heat the home in colder climates. The opposite takes effect in warmer climates.
Minimizing East/West Glazing: East and west-facing windows are notoriously difficult to shade during harsh summer afternoons. Minimizing their size or protecting them with external shading keeps cooling loads down.
2. High-Performance Glazing
Windows are typically the weakest thermal link in a building envelope, leaking heat in winter and letting it pour in during summer. Although standard aluminium single glazed windows can work effectively, things like poor orientation, high window to floor ratios means you may have to look at:
Double Glazing: Upgrading to double-glazed windows with low-emissivity (Low-E) coatings is sometimes essential to clear the 7 star threshold.
Framing Materials: Thermally broken aluminum, uPVC, or timber frames dramatically cut down thermal transfer compared to standard aluminum frames.
3. Upgraded Insulation
Insulating your home to levels slightly above baseline minimums pays off instantly in star ratings.
Ceilings & Walls: Moving to higher R-values (such as R6.0 to R7.0 for ceilings and optimized R-values for external walls) prevents conditioned air from escaping.
Installation Quality: Insulation must be installed without gaps or compression; even minor compression around wall studs can drop thermal performance significantly.
4. Effective Shading and Air Tightness
Eaves and Awnings: Correctly sized eaves block high summer sun while letting in warming winter rays.
Airtightness: Sealing gaps around exhaust fans, windows, and downlights prevents unwanted drafts and keeps your indoor climate stable.
Benefits Beyond Compliance
While meeting the 7-star mandate is legally required for new residential builds, the long-term advantages make the upfront design effort worthwhile:
Lower Energy Bills: Cutting heating and cooling loads by up to a quarter translates directly to significant savings on electricity and gas.
Superior Comfort: Say goodbye to freezing winter bedrooms and scorching summer living rooms. A 7-star home maintains a stable, comfortable indoor temperature naturally.
Future-Proofed Property Value: Energy-efficient homes are increasingly favored by buyers and renters who look at star ratings and utility running costs as key purchasing metrics.
Tips for a Smooth Approval Process
Engage Early: Involve your energy assessor or BASIX consultant at the preliminary architectural design stage rather than treating compliance as an afterthought.
Avoid Costly Redesigns: Making minor adjustments to window sizes or insulation specifications on paper is easy; changing structural plans after engineering drawings are complete is expensive.
Look at the Whole Picture: Remember that your thermal rating (7 stars) works in tandem with your Whole of Home appliance efficiency score. Balancing both ensures your certificate is issued without delays.
Are you ready to see if your current plans meet the criteria?
Consult Assessify early in your design phase to ensure your home meets the standards required in order to have a nice & relaxed plan submission. Get a Free Assessment Quote
Written by Mark Zangari, NatHERS Consultant @ Assessify
Mark Zangari is a building compliance and sustainability specialist at Assessify, with experience supporting residential development approvals across Australia.
They work closely with builders, designers, developers & home owners to navigate NatHERS requirements, development applications and construction compliance.
With a focus on practical, regulation‑aligned guidance, Mark helps clients identify compliance risks early, avoid approval delays, and ensure sustainability commitments are met throughout the design and build process.