New Zealand’s sustainability rating tools measure fundamentally different things, which is the source of most of the confusion around them. Green Star rates what was designed and built. NABERSNZ rates what a building actually consumes in operation.
Understanding which one answers your question is the difference between a credential that means something to your tenants and investors and a logo on a website.
What each one certifies
| Credential | What it rates | Basis | Who holds it |
|---|---|---|---|
| Green Star Fitouts | Design and construction of an interior fitout | Assessed against credit criteria | Tenant or landlord, per project |
| Green Star Buildings | Design and construction of a whole building | Assessed against credit criteria | Developer or owner, per building |
| Green Star Performance | Operational performance of an existing building | Ongoing assessment | Owner or asset manager |
| NABERSNZ | Measured energy efficiency in operation | 12 months of actual consumption data | Owner or tenant, per building or tenancy |
The distinction that matters most is between assessed and measured. Green Star assesses a design against criteria. NABERSNZ measures actual energy consumption over twelve months and normalises it for hours of use and occupant density. A building can achieve a strong Green Star rating and still perform poorly if it is operated badly or occupied differently than modelled.
Green Star for fitouts
Green Star is the New Zealand Green Building Council’s rating tool. The fitout tool assesses the interior rather than the base building, which makes it the relevant instrument for a tenant occupying part of a building they do not own.
Assessment categories typically cover energy use and efficiency, indoor environment quality including air quality, thermal comfort, acoustics and daylight, materials selection with emphasis on low embodied carbon and responsible sourcing, construction and operational waste, water efficiency, and innovation.
New Zealand examples include Tonkin and Taylor at 6 star, Foodstuffs North Island at 6 star, and Country Road Newmarket at 5 star.
Confirm current credit criteria, rating thresholds and certification fees directly with the NZGBC, as these are updated periodically.
NABERSNZ
NABERSNZ rates measured energy performance on a scale of one to six stars using twelve months of actual consumption data. Three rating types exist: base building for landlord controlled services, tenancy for the occupier’s own energy use, and whole building.
For a fitout project the tenancy rating is the relevant one, and fitout decisions around lighting, controls, equipment selection and supplementary cooling feed directly into it. NABERSNZ has been expanding beyond its original office focus toward other building types.
Because it is measured rather than modelled, NABERSNZ is harder to achieve and more credible commercially. It also rewards good operation rather than good intentions.
Does certification deliver commercial value?
The evidence in New Zealand is reasonably good.
JLL research found Green Star certified offices in New Zealand command sales premiums ranging from 3.7 percent for a 4 star rating to 7.5 percent for 6 star, and rental premiums from 1.5 percent to 2.25 percent across the same range. Buildings holding both Green Star and NABERSNZ ratings showed the highest occupancy and the lowest vacancy.
Tenant experience data supports the operational case. Green Star Interiors tenants including Generator Bowen Campus have reported electricity use 30 to 40 percent lower than comparable space.
On the investor side, the Green Building Council of Australia reports that around 22 percent of investors now assess circularity, a proportion that continues to rise.
Set against that, certification carries genuine cost: registration and assessment fees, sustainability consultant fees, modelling, and additional documentation effort across the project team. It can add time. Some credits require specification decisions that cost more than the conventional alternative.
The pragmatic middle position
Many organisations design and build to the standard without pursuing formal certification. This captures the operational benefit, the indoor environment quality benefit and the substantive environmental outcome without the certification cost.
The trade off is that you cannot demonstrate it externally with a recognised mark. For an organisation with public ESG commitments, institutional investors or government tenants, that demonstration is often the entire point, and the certification cost is the price of credibility. For a small tenancy on a short lease, it frequently is not.
The decision should turn on who needs to be convinced, not on whether the environmental outcome is worth pursuing. The environmental outcome is worth pursuing either way.
Where the carbon reporting requirements are heading
MBIE’s Building for Climate Change programme includes a Whole of Life Embodied Carbon Emissions Reduction Framework, which introduces reporting requirements first and phased caps subsequently.
The practical implication is that measurement is becoming mandatory before reduction becomes mandatory. Organisations with their own emissions reporting obligations increasingly need supply chain carbon data from their contractors, and a contractor who has never measured cannot supply it. Their emissions become an unquantified gap in your own reporting.
This is worth raising at procurement rather than after award, because retrofitting measurement onto a project already under way rarely produces usable data.
Practical steps if you are certifying
Decide before design starts. Several credits depend on decisions made in the first few weeks. Retrofitting a rating onto a developed design is expensive and usually produces a lower result.
Check the base building first. Many fitout credits depend on base building attributes such as sub metering, services efficiency and daylight access. Assess this before signing the lease, not after.
Engage the contractor early. Construction waste diversion, responsible sourcing documentation and low emitting material substitution all sit with the contractor and must be built into procurement and site process from the start.
Plan the evidence. Certification is substantially a documentation exercise. Product declarations, waste weighbridge records by stream, commissioning reports and modelling all need collecting as the project proceeds. Reconstructing them afterwards is usually impossible.
Frequently asked questions
What is the difference between Green Star and NABERSNZ? Green Star assesses the design and construction of a building or fitout against credit criteria. NABERSNZ measures actual operational energy performance using twelve months of real consumption data. Green Star rates what was built, NABERSNZ rates how it performs.
Can a tenant certify their fitout without the building being certified? Yes. The Green Star fitout tool is designed to rate an interior independently of the base building. Some credits are influenced by base building attributes such as sub metering and daylight, so the building you choose affects what rating is achievable.
Is there a rental premium for green certified space in New Zealand? JLL research found Green Star certified New Zealand offices command rental premiums of 1.5 percent for 4 star up to 2.25 percent for 6 star, and sales premiums of 3.7 to 7.5 percent across the same range, with the highest occupancy and lowest vacancy in buildings holding both Green Star and NABERSNZ ratings.
Does a sustainable fitout cost more? Some elements do and some do not. Efficient lighting and controls, good commissioning and sensible material selection often pay back through lower running costs. The clearest additional costs are certification and consultancy fees and, on some projects, specific credit driven specification upgrades. Designing to the standard without certifying captures most of the operational benefit at lower cost.
Is certification required by law in New Zealand? No. Green Star and NABERSNZ are voluntary. The Building Code sets mandatory minimum requirements including energy efficiency provisions. MBIE’s Building for Climate Change programme is introducing whole of life embodied carbon reporting with phased caps to follow, so measurement is moving toward mandatory ahead of reduction.
Related reading
- The Hidden Carbon Cost of Fitout Churn
- Construction and Demolition Waste in New Zealand: Where It Goes and How to Divert It
- Auckland Office Vacancy, Incentives and the Flight to Quality
Sources
- New Zealand Green Building Council, Green Star Fitouts
- NABERSNZ programme information
- JLL, Turning green to gold, New Zealand green building value research
- Green Building Council of Australia, investor circularity data
- Ministry of Business, Innovation and Employment, Building for Climate Change and the Whole of Life Embodied Carbon Emissions Reduction Framework
Refresh schedule: rating tool criteria, thresholds and fees are updated periodically. Verify against current NZGBC and NABERSNZ documentation at each review and at minimum every six months.
This article is general information. Confirm current criteria and requirements directly with the relevant certifying body.