More than just measuring and certifying – how a NABERSNZ assessor can become a trusted partner
As NABERSNZ grows in popularity, building owners and tenants are looking at using its tools to do more than just measure and certify. It’s increasingly being used as a vital part of improving performance and comparing efficiency across a property portfolio. Some property companies are bringing in an experienced assessor into their organisation as strategic team members or training up staff internally to become an assessor.
At the heart of the programme is the NABERSNZ assessor. We spoke to Auckland-based assessor Dave Annable to find out what’s involved and get some ideas for potential and existing NABERSNZ users about getting the most out of the programme.
Meet the assessor
Dave is a Mechanical Building Services Engineer with RME Solutions, with experience across new builds and refurbishment projects. He particularly enjoys working on existing buildings where improvements can deliver both energy and financial savings for the client.
“Getting a NABERSNZ rating has been proven to lead to reductions in operating costs, often without significant capital investment,” says Dave. It’s also an important tool for verifying a building or tenants energy consumption, and for targeting improvements.”
As New Zealand faces rising gas costs and increasing pressure to decarbonise, the role of NABERSNZ assessors is becoming more influential than ever.
Their work goes far beyond obtaining ratings: assessors provide ongoing monitoring, operational insights, and practical recommendations that help building owners cut energy waste, reduce emissions, and improve financial performance.
A building owner can get a NABERSNZ assessment, file it and then ignore it until next time if they want – but that’s not the sort of work that drives Dave.
He’s an example of an assessor who provides something more than a simple check and endorsement - offering a way for clients to drive meaningful change.
Rising demand
Demand for NABERSNZ has surged in recent years, he says, with building owners increasingly motivated by:
- The need to report performance to boards and investors.
- Tenant expectations for efficient, low carbon buildings with lower operational costs.
- Sustainable finance (bank lending, green bonds, etc) requirements linked to verified energy performance.
- Rising gas prices that make inefficient systems financially untenable – NABERSNZ has emission factors built in that reward fully electric buildings that rely on our low-emissions grid.
Since 2021, Dave has seen NABERSNZ “really take off” due to these market pressures, with many clients now seeking not just ratings but a pathway to continuous improvement.
Assessment
Dave begins with a high-level review of each building’s metering, plant, documentation, and operating patterns. This is often followed by detailed walkthroughs and a review of the Building Management System (BMS) to identify waste and uncover opportunities for savings.
Common issues he finds through his assessment include:
- HVAC systems starting several hours earlier than needed.
- Temperature setpoints varying wildly across open plan offices.
- Newer, complex buildings needing commissioning or tuning.
- Older buildings running inefficiently overnight.
Often simple operational changes — such as standardising temperatures or resetting start up schedules can achieve energy savings of between 10 to 20% at no capital cost.
At Kiwi Property, monthly performance tracking has enabled Dave to identify waste, optimise systems, and reduce energy consumption across multiple buildings.
Significant savings were achieved purely through monitoring and operational improvements. This performance uplift was later strengthened by the installation of heat pumps, which further reduces reliance on gas.
It’s results like this that show the value of using NABERSNZ not just as a rating tool, but an ongoing management mechanism. Another one of Dave’s clients uses NABERSNZ to compare buildings within its portfolio, enabling better decision making across multiple assets.
This ability to benchmark similar buildings helps identify where inefficiencies exist and where investment should be prioritised.
It’s a lot about the gas
Gas usage has a strong negative influence on NABERSNZ ratings, with many clients finding they cannot achieve a 5 to 5.5 star rating without making the move away from gas, says Dave.
He has seen some key trends in this area recently, including:
- Gas prices increasing dramatically, strengthening the financial case for change.
- Many clients are considering electrification but are still uncertain about timing and technology maturity.
- Commercial heat pump water systems continue to improve, with newer units reaching temperatures that can replace traditional boilers.
The combination of higher gas prices and updated NABERSNZ emissions factors has amplified the penalty for gas dependent buildings.
So, what should someone new to NABERSNZ know about getting an assessment?
Advice for those new to NABERSNZ
New clients often find the data, occupancy, and metering documentation requirements challenging, says Dave — but these are essential components of the NABERSNZ methodology. It’s crucial to know exactly who is in a building and when.
A typical assessment involves:
- Data collection and validation of metering, particularly in multi-tenanted buildings with extensive submetering.
- A site visit to verify plant, metering, and operational conditions.
- Building management system reviews to detect irregularities and inefficiencies.
- Quarterly meetings for those clients wanting ongoing monitoring.
Dave emphasises transparency when making these assessments. “It’s crucial to
help clients understand what is required and why, without overselling the process,” he says.
In line with many assessors, Dave offers an ongoing service which includes regular updates, reporting, and collaboration with contractors or facilities managers.
His advice for those looking for a NABERNZ assessor is to find out what extras you can get for the price you’re paying. What does this price get you – is it an annual rating or does it come with quarterly updates?
As NABERSNZ grows in popularity, professionals like Dave Annable are clearly showing how the act of measuring and certifying energy performance can spark the beginning of a meaningful and ongoing collaboration.
- Movers and Shakers Q & A with Dave Annable(external link)
- Find a NABERSNZ assessor(external link)
- Introduction to NABERSNZ | NZGBC(external link)
- See a list of buildings certified with the NABERSNZ Energy for Office rating tool: