Green Star Performance is the only Australian rating tool that assesses how an existing building is run, across the full breadth of sustainability rather than energy alone. Green Star Performance takes a holistic view of how an existing building is operated, covering areas such as governance, occupant health, resilience, resource use, nature and decarbonisation. NABERS complements this by providing independently verified performance ratings across areas such as energy, water, waste and indoor environment.
Green Star Performance V2 has been rebuilt to align with the frameworks investors and lenders already use, which makes a certified rating a useful input to sustainability disclosure rather than a separate exercise.
What V2 looks like
Version 2 moves from nine categories to eight, with a new Leadership category replacing Project innovation and Custom innovation challenge and recognising organisations that go beyond compliance to drive change across the industry. Across those eight categories sit 37 credits worth 110 available points, and the points you earn determine your star rating from 1 Star to 6 Star.
Two structural changes are worth knowing before you start. Sector specific credits are gone, which means a much wider range of building types can now be rated and benchmarked on a consistent basis. And most credits now have three levels of achievement rather than one: Credit Achievement as the entry standard, High Performance where you exceed it, and Exceptional Performance for sector leading outcomes. Each level carries additional points.
The Clean Air Credit is a good illustration:
- Credit Achievement requires targets and regular inspection of the HVAC system.
- High Performance adds monitoring of carbon monoxide and carbon dioxide.
- Exceptional Performance extends to particulate matter and other pollutant sources.
You can sit at different levels across different credits and build up over successive years.
What the process involves
Green Star Performance certification is managed by GBCA. It is a document-based assessment, submitted online and reviewed by an independent third party assessor, with up to two rounds of review before a rating is awarded.
The sequence looks like this: plan and scope, register, set your data period, decide which credits to target, assemble the evidence, submit, work through Round 1 and if required Round 2, receive your certified rating, then repeat annually.
Where a partner fits in
It is tempting to treat a Green Star Accredited Professional as someone you bring in to lodge the submission. In practice, the decisions that determine your rating are made months earlier: which credits are worth targeting, whether your NABERS ratings will still be current at submission, whether a policy can be written now rather than needing twelve months of history behind it, and whether the star rating you have in mind is realistic.
Those questions are hard to answer without knowing the tool in detail, and getting them wrong is expensive, because you find out at Round 1.
The division of labour through the rest of the project is reasonably clear. Your accredited professional interprets the credits, sets the strategy, manages the relationship with GBCA including any technical questions, reviews the evidence as it comes in, and lodges the submission. Your site teams, facility managers and property managers supply the data and implement the procedures on the ground.
Step 1: Plan early, well before you register
This is the step teams most often underestimate, and it is the point to bring in a Green Star Accredited Professional.
Starting the conversation two to three weeks before registration lets you resolve the questions that shape everything downstream: which credits are worth targeting, what evidence already exists, whether the building meets the eligibility criteria, and whether any technical questions need to be lodged with GBCA before you commit.
For a portfolio, this is not optional. Twenty buildings generate a lot of documentation, and the difference between a smooth submission and a painful one is almost entirely decided here.
The practical output of this stage is a gap assessment: what your existing NABERS ratings, policies and monitoring already cover, against the credits and minimum requirements for the star rating you are targeting.
Step 2: Register the project
Registration is done online through GBCA’s Green Star Project Manager. It involves confirming eligibility, providing project and applicant details, accepting the Certification Agreement and paying the certification fee. Portfolios upload their asset list using GBCA’s template.
Only registered projects are permitted to say publicly that they are targeting a Green Star rating.
Step 3: Set your data period
Version 1.2 had a “performance period”. Version 2 replaces this with the data period, or annual certification cycle.
At initial submission you determine the twelve months of data the rating will assess, and it cannot be stale. If you are using a NABERS rating for energy and water, it needs to be current at submission, so an expiring rating is a problem worth catching early.
From there, each annual resubmission must follow on without a gap between certifications. If your first submission runs on a calendar year, subsequent years do too.
Step 4: Work out which credits to target
Credits in V2 break down into a few types. The two that matter most for planning are policy credits and action credits.
Policy credits capture formal organisational commitments: sustainability policies, waste management strategies, environmental management plans. They require management engagement and documentation, but they are relatively straightforward, and this is where V2 is notably more flexible than its predecessor. Policies generally need to be active and in use by the time you submit, or shortly after depending on the credit intent. That means they can be developed during the project rather than needing to have been in place across the full data period, so this is work your accredited professional can do alongside you rather than something you need to have completed before you start.
Action credits cover delivery: your energy, water, waste and indoor environment data. These need updating every year to maintain certification, they take more time and coordination, and they carry more points. They are also the credits that demonstrate you are actually doing what your policies say.
If you are starting from a low base, the sensible entry point is to register, meet the minimum credit criteria, then target energy and water. If you already hold a NABERS rating, those credits become straightforward and can be worth substantial points where the building performs well. Indoor Environment is the next natural target, both because the testing produces clear comparable results and because it demonstrates something visible to tenants.
Step 5: Use the NABERS pathway
For energy and water, The NABERS pathway is generally the most straightforward option for the Energy Use and Water Use credit. After your initial Green Star Performance rating, choosing not to use the NABERS pathway requires justification through an approved technical question. Over the next three years, projects will be expected to move to the NABERS pathway wherever a NABERS rating exists for that sector.
Note that availability varies by sector and by rating type. Logistics facilities for example, have a NABERS Energy pathway but not water.
For portfolios with a mature NABERS program, this is the single biggest efficiency in the tool. The data your team already produces annually carries straight across.
Step 6: Assemble the evidence and resolve the grey areas
This is where most of the four to six months of active work sits. Working from the Submission Guidelines, templates and scorecard, the team compiles the evidence for each credit claimed.
Where a requirement is unclear or an alternative compliance pathway is being considered, a Technical Question can be lodged with GBCA. These are lodged by your accredited professional, who manages the response and folds it into the submission. Five Technical Questions are currently included within the standard certification fee, with additional questions attracting a modest fee. GBCA aims to respond within 10 working days, and the formal response takes precedence over the guidance in the credit itself. It is therefore far better to resolve genuine uncertainty before submission than to debate it during assessment. Each registered project is also assigned a GBCA technical coordinator to help navigate the process.
Step 7: Round 1 and Round 2 assessment
Submission itself is quick. What matters is that the pack is clean and legible, so the assessor can see immediately what has been claimed and why.
GBCA’s standard turnaround is six weeks for Round 1 and four weeks for Round 2, although project teams should allow additional time around peak submission periods such as EOFY and end of year. Each credit comes back as points awarded, points to be confirmed, or points not awarded with an explanation.
Where credits are marked to be confirmed, you address the assessor’s comments in a Round 2 submission. New credits can also be claimed at Round 2, which is a useful lever if the Round 1 result falls short of the target. If the comments are unclear, you can request a Clarification of Assessment Comments rather than guessing.
Step 8: Certification
The result is a certified rating valid for twelve months, from 1 Star through to 6 Star, with each star level requiring both a minimum points total and a specific set of mandatory credits.
For portfolios, every building in the submission receives its own star rating, and the portfolio receives a rating of its own based on the area weighted average of the assets included. That combination is useful: individual assets can be promoted on their own merits while the portfolio result tells the organisational story.
Step 9: Recertify annually, and plan for the Climate Positive Pathway
Maintaining a continuous rating means registering and submitting every year, but not rebuilding the submission from scratch. Version 2 only requires the information relevant to that year. Energy and water need fresh data each cycle. Policy credits generally need review rather than reissue, and some credits hold for several years provided nothing material changes.
The part worth planning for now is the Climate Positive Pathway. Australia’s national target is 2050. GBCA has set 2040 for all Green Star Performance rated buildings to be climate positive, a full decade earlier. Carbon neutral means a building has reduced and offset its operational emissions. Climate positive goes further, generating a net environmental benefit by preventing or removing more emissions than the building produces.
The requirements tighten year on year. Practically, this means electrification, renewable electricity and responsible procurement need to sit on a five to ten year plan, not a twelve month one. It is worth asking now whether the rating you hold today is one you can still hold in a decade.
A note on the net zero action plan, since it is a common question. It can be written for you, but it needs to be signed off, published and owned internally as part of your strategy. The point is that you improve against it year on year, which only works if the organisation stands behind it.
Where projects come unstuck
Four things account for most of the friction.
Data arrives late, or arrives wrong. Providing data early gives the team time to find the errors before they matter.
Data arrives in bulk rather than as samples. For portfolios, sample documentation is permitted for many credits. Sending everything for every asset creates thousands of pages that slow the review down without adding a single point.
Testing does not meet the guidelines. Specialist contractors deliver the work behind the data driven credits, including indoor air quality testing and NABERS ratings. If a report is not produced in accordance with the Green Star Performance V2 guidelines, it cannot be used, and the points are lost.
Deadlines slip. GBCA schedules assessors, so a late submission does not simply move your date, it can push you well beyond it.
The antidote to all four is strong planning: shared document repository, a tracker with named owners and deadlines, and regular check-ins.
Watch our webinar for more details about Green Star Performance V2:
How NettZero can help
The hardest part of Green Star Performance V2 is rarely the technical requirement of any single credit. It is knowing which evidence you already hold, which credits your NABERS program already carries, where the real gaps sit, and how to sequence the first submission so that subsequent years are lighter.
NettZero’s Green Star Accredited Professionals work alongside our NABERS Accredited Assessors, so the team that already understands your meters, boundaries and evidence sources carries that knowledge directly into your Green Star Performance submission.
If you are considering Green Star Performance V2 for a building or a portfolio, contact the NettZero team to discuss a gap assessment and understand where you currently sit.