NABERSNZ and government office buildings

The National Australasian Built Environment Rating System – New Zealand (NABERSNZ) is a system for rating the energy efficiency and water efficiency of office buildings and office tenancies. While NABERSNZ offers both energy and water ratings, the requirement for government-occupied office buildings is the energy rating only. Water ratings are optional. 

Criteria for NABERSNZ rating

NABERSNZ rating requirements apply to office space occupied by mandated agencies unless entering a short-term lease (less than 4 years in total, including renewals). It is also recommended practice for non-mandated agencies.

Government property mandate

The three types of NABERSNZ ratings are:

• Base build rating: required where a mandated agency occupies 2,000m2 or more within a single building, and occupies 50% or more of the building’s total Net Lettable Area (NLA).  This measures the energy efficiency of a building’s core services (such as central heating and cooling, lifts and common area lighting).
• Tenancy rating:  required where a mandated agency occupies 5,000m2 or more within a single building. This measures the energy use of the area occupied exclusively by the tenant. 
• Whole building rating: combines a base building and tenancy rating. This rating should only be used where an agency meets the base building rating criteria, but sub-metering does not allow base building and tenancy energy use to be measured separately.

Where multiple mandated agencies occupy the same building (co-located or co-tenanted), the above requirements are based on their combined occupied area.

Agencies may arrange one shared rating for the building.

Use the self-assessment tool below to confirm whether you need a NABERSNZ rating and what type of rating to obtain.

NABERSNZ self-assessment tool

NABERSNZ ratings targets for agencies

• NABERSNZ gives a star rating between 1 and 6 stars.
• Agencies entering a new lease or renewing an existing lease should aim for a rating of 5-stars or above and achieve a minimum rating of 4-stars. Agencies planning a new build must achieve a minimum rating of 5-stars.
• NABERSNZ ratings are valid for 12 months from the date of assessment.
• Agencies that meet or exceed the minimum required star rating only need to obtain a new rating every three years.
• Where the minimum required rating is not achieved, an agency must implement an improvement work programme within 12 months, and re-rate annually until the minimum star rating is met.

Reporting NABERSNZ ratings to the Government Property Office (GPO)

• Mandated agencies must report NABERSNZ ratings for office space meeting the above criteria to GPO. This supports transparency and ongoing performance monitoring.
• Where an agency is moving into new leased space, completing a major refurbishment, or occupying a new building, a NABERSNZ rating must be obtained once the workplace has been operational for a minimum of 12 months.
• If your agency has started or already completed a NABERSNZ assessment, complete the form below and email to the Government Property Office.  
• We will then add this information into the Government Property Portal.

NABERSNZ re-rating requirements

• Buildings or tenancies that meet or exceed the minimum required star rating only need to obtain a new rating every three years, counted from the date the previous rating was issued.
• Where the minimum required rating is not achieved, an improvement work programme must be developed within 12 months.
  • Base building ratings: Improvements are the responsibility of the landlord, with agency input as required.
  • Whole building ratings: Improvements require a collaborative approach between the landlord and the agency.
  • Tenancy ratings: Improvements are the responsibility of the tenant, with landlord involvement where required.
• The building or tenancy must then be re-rated annually until the minimum star rating is met, counted from the date the previous rating was issued.
• Once the minimum rating is achieved, the three-year re-rating cycle applies.

Arranging and funding a NABERSNZ assessment

NABERSNZ ratings must be carried out by NABERSNZ Accredited Assessors.

• Assessors are procured directly from the market and set their own fees.
• Tenancy assessments are usually paid for by the agency.
• Base build assessments are usually paid for by the landlord; this can be negotiated between the tenant and the landlord. Assessment costs — NABERSNZ
• Base building and whole building ratings require access to building level energy data, which is typically held by the landlord. Collaboration between agencies and landlords is often needed to complete an assessment.

More information

• Watch EECA's NABERSNZ intro video — YouTube
• To find out more about NABERSNZ visit the NABERSNZ website
• A NABERSNZ Accredited Assessor can help with technical queries, including matters relating to metering, data availability, and the appropriate rating type.
• Agencies who want to better understand their building’s likely performance before engaging an assessor can complete the free online NABERSNZ self-assessment tool available on the NABERSNZ website. A self-assessment is optional and does not replace an accredited assessment. However, it can help agencies identify potential improvement opportunities early. Self-assessment tool — NABERSNZ

For more advice and support on NABERSNZ:

Email the Government Property Office