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 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
Ducted Fan Coil Units DABv1 May 2022 9 - Indoor Air Quality Ventilation System Attributes Link
Approved Ruling:

Are ducted fan coil units/VAV boxes required to provide access to both sides of fan coil units?

No, project teams do not have to provide access to both sides of coils for cleaning and maintenance purposes of such systems, provided the following conditions are met:

1. Design teams may provide access to the upstream side of fan coil units/VAV boxes where the coils are protected by a filter rated at MERV 8 or higher and:

  • Provide heating only; or,
  • Provide cooling only with the coil assembly no more than 4 rows deep; or,
  • Provide dual heating/cooling with the coil assembly no more than 4 rows deep

and

2. For fan coil units or air handling units located within a ceiling void, in addition to the above criteria, the project team must fully demonstrate safe access for cleaning and maintenance. This may include:

  • Access panels in unit / ductwork is in close proximity to the coil to be cleaned.
  • Access panels in the ceiling below the unit is in close proximity to the unit / ductwork access panel.
  • The upstream surface of the coil must be accessible within 1m of the ceiling panel.
  • For projects where a wall-mounted unit is installed, the project team must demonstrate that access is provided to one side of the coil for cleaning and maintenance purposes. The project team must also demonstrate:
  • The filter system used can achieve the same outcome as MERV 8 filter and;
  • Coil assembly is no more than 4 rows deep.

Documentation Requirements:

Please provide the following in your submission:

  • Evidence that all moisture-producing and debris-catching components such as cooling coils, heating coils, humidifiers and filters in the air handling unit are able to be sufficiently cleaned and maintained through single sided access.
  • Section drawing demonstrating any ceiling units can be safely reached through the ceiling access panel.
  • Plan drawing showing 100% of the upstream surface of the coil is accessible within 1m of the ceiling panel, allowing for obstructions.
  • A copy of this response.