Skip to content
About us
Get to know the New Zealand Green Building Council
Membership
Meet and join our community
Our network for students and young professionals
News and advocacy
Keep up to date
Green buildings
Getting started
Certify a commercial building project
Certify a community development
Certify a building's operational performance
Operate at Net Zero
Green homes
Certify the design and construction of a new home
Improve your existing home
Training and events
Upcoming events & training
Professional development
Cart
Find a professional
Login
Search

Search

 Green Star Technical Clarification Rulings

Technical Clarifications for Green Star represent our answers to Technical Questions submitted by projects, and provide further guidance and reference to others. The list is regularly updated.  

There are two types of Technical Clarifications listed in the table below:

General Clarifications

These are extensions to the guidance provided in the Submission Guidelines. They clarify and sometimes supersede the original Credit Criteria or 
Compliance Requirements. General Clarifications set precedent for future project teams to follow. Should a project team wish to apply a general clarification to its project, there is no requirement for further Technical Questions to be submitted. NZGBC Assessors will also use them as precedents to assess submissions.

Project Specific Clarifications

These are published as references for other projects but, unlike General Clarifications, they do not set precedent. They often relate to special 
situations where multiple prerequisites exist for a particular project and are less likely to reoccur to another project. Therefore, rulings set for Project Specific Clarifications are often conditional and will likely vary for other projects. Each project still needs to submit its own Technical Questions and provides evidence relating to its own building in order to have a similar ruling approved for that specific building. 

Should you wish to apply any Technical Clarification for legacy rating tools to your projects, please submit a Technical Question to the NZGBC to 
explain why and how it applies. You can access the online Technical Question form here

Technical Question Title Tool Version Date Released Credit Name Sub-credit Name TC Link
2.1 Environmental Performance Targets DABv1, DABv1.1, Green Star Buildings NZ May 2025 2 - Commissioning and Tuning, 3 - Verification and Handover Environmental Performance targets Link
Approved Ruling:

This credit requires the design team to define the environmental performance targets (EPT) for the project based on the design. As part of this, they must outline the operational and maintenance requirements specific to achieving the performance targets. Energy or water use are not just defined by the way the building and its systems are built, but by how those systems are operated and maintained.

This document is expected to be initiated in the early stages of design. If the decision to target Green Star certification occurs late in design, then the EPT document should be prepared as soon as possible after that decision is confirmed. If the decision to target Green Star occurs after the design stage is complete the project team should submit an eligibility TQ to the NZGBC. This document is expected to be a live document during the design process, being finalised at the end of the design stage.
 
The document required for this credit is intended to be useful to the project and not just created for the purpose of achieving Green Star compliance. This should be considered when writing the document by the design team.
 
The purpose of the credit is to provide a record of the intent of the design (design narrative and rationale) and expected operational and maintenance requirements. It is also intended to show how the performance targets are metered and can be monitored. This record can then be used:
  • To help the Client understand what has been designed, how it responds to their expectations and what the ongoing requirements for the systems will be.
  • During construction to understand if any changes to the systems selection or design could create a deviation away from the environmental performance targets.
  • To identify whether the built systems align with the design and if not enable the deviation to be identified. For example, has the system been set up to operate as it was intended?
  • By the fine-tuning team during the tuning period so they can check meter readings against the relevant environmental performance budget. Also, to assist them with understanding why an energy, water or IEQ target is not being achieved. Is it a result of a deviation in operational expectations, or is a maintenance activity required to correct the performance issue?
  • By the FM to understand the design intent of the systems and if necessary, assist with performance monitoring. For example, where a building owner commits to environmental performance monitoring under credit 5.1(DABv1.1). Any built deviations to the systems would need to be identified to enable the document to be useful. These built deviations are not expected to be recorded in the document for credit 2.1.1 (DABv1.1).
This document should not be made up of spec clauses as these do not describe the design intent required for the credit. Design parameters may be copied from the specs however, for example, the design conditions for the HVAC system.
 
The operational requirements in the document provided for this credit should include both automatic and manual control of the system, including efficient use. As an example of efficient use, for a lighting system:
  • Setting up time clock control to meet the working hours of the users.
  • Enabling occupancy sensor control when the lighting time clock control is manually overridden to ensure the lighting will turn off automatically when the space is not occupied.
  • Ensuring the occupancy sensor control only controls the lighting zone in its vicinity, not a larger area or the whole floor.
  • Ensuring the occupants understand how the lighting can be used efficiently including minimising manual control, turning the lighting back on to automatic control when manual control is no longer required. Clear guidance to be recorded in the Building User Guide.
The maintenance requirements in this document are expected to be outlined. They should include consideration of performance maintenance, not just preventative or routine maintenance requirements. Detailed maintenance procedures are not required only a list of maintenance activities, frequency, and troubleshooting. The purpose of recording this information in this document is to communicate to the building owner the extent of operations and maintenance requirements there will be for the selected systems. 

An example is provided below.

Maintenance activity

Frequency

Indication maintenance might be required

Replace filter

Every 12 months
  • Dirty filters can cause an increase in energy use of the HVAC system and/or a decrease in the air flow from the unit.
  • The filter may be visibly dirty or grey.
  • Dust may have accumulated around vents.

For the targets, metering and monitoring part of the EPT documentation:

 

DABv1.1

Buildings

At Design Review stage

Credit 6 not being targeted – EPT document should contain the metering and monitoring information for credit 2.1.1.

 

Credit 6 being targeted – the EPT document can reference the Monitoring Strategy developed for credit 6 if this is available at Design stage otherwise is required to contain the metering and monitoring information for credit 2.1.1.

EPT document can reference the Monitoring Strategy to avoid replication of information. Any information not covered by the Monitoring Strategy but required under ‘Environmental Performance Targets and Information’ in the SG should be included in the EPT document. If the Monitoring Strategy is not yet available then the EPT document must contain all targets, metering and monitoring information required under ‘Environmental Performance Targets and Information’ in the SG.

At As Built stage

Credit 6 not being targeted – EPT document should contain the metering and monitoring information for credit 2.1.1.

 

Credit 6 being targeted – the EPT should reference the Monitoring Strategy developed for credit 6.

 

Note that where projects go through Design Review assessment with a compliant EPT document, no further updates to this document would be required at the As Built stage.  

EPT document should identify the targets but can reference the Monitoring Strategy also required for credit 3 to avoid replication of information.

 

Note that where projects go through Design Review assessment with a compliant EPT document, no further updates to this document would be required at the As Built stage.  

 

For DABv1.1 projects only:
Where a Monitoring Strategy is not available or inadequate (DABv1.1 only and only at design stage as per the above table) the EPT document should clearly include a sufficient description of the metering and monitoring approach. For example, including the metering diagram but also including an easy way for the reader to understand which meter relates to which set budget. 

As an example, this could be presented in the following way:

Energy end use

Performance target (kWh/a)

Associated meters

HVAC

12,000

CM3, CM5

 

Where CM3 and CM5 are the two meters in the building that read the HVAC energy use as identified on the meter diagram included in the document. Note that the meter numbers required in this table would be as identified on the meter diagram also provided in the document.
 
The breakdown of targets per system/use presented in the EPT should align with the metering breakdown. This allows these budgets to be confirmed in operation. Projects that meet the small buildings exception presented under credit 6 (DABv1.1) or credit 3 (Buildings) need only provide a single energy and single water target, rather than per system/use.
The monitoring information here is not expected to be as detailed as the TM39 monitoring strategy required for credit 6, but it should outline the process. For example, including the monitoring frequency, the process for rectification if a budget is being exceeded, who is responsible, regularity of reporting of environmental performance, and what gets reported to who.
 
For DABv1.1 and Buildings projects:
Fire, communication, IT, security and lift systems can be excluded from the EPT documentation.
 
Efficient use (DABv1.1) should detail how the automatic controls enable efficiency, but also how efficiency can be managed through manual control. Examples include:
  • Not opening windows when the mechanical ventilation is operating.
  • Setting the lighting to automatically operate during the main business hours only, with sensor controls at all other times.
  • If the automatic lighting control is overridden to turn the lighting back to the automatic system as soon as manual control is no longer needed.