NABERS: 25 year program overview

Abstract

In 2024, the National Australian Built Environment Rating Scheme (NABERS) celebrated 25 years since the launch of its first rating in 1999. This paper provides an overview of the scheme’s development and operation as well as showing data trends gathered from NABERS energy ratings. NABERS is one of few rating schemes internationally that focusses entirely on the measured in-use performance of existing buildings rather than design features. Buildings are rated based on their performance (e.g. energy use, water use from bills) relative to empirically derived benchmarks for an equivalent median building. NABERS also has a Commitment Agreement process for new buildings, which enables new building projects to commit to a post-construction NABERS rating. In the financial year 2023–24, NABERS certified 2228 office buildings in Australia, covering over 24 million m² of office space. Over the life of the program, more than 4200 unique office buildings have been rated, representing the majority of the office sector in Australia. NABERS has catalysed significant improvements in operational energy efficiency in the office and shopping centre sectors via a combination of market-based and regulatory drivers. NABERS ratings are mandatory for office buildings seeking to sell or lease spaces greater than 1000m². The success of NABERS is based on its simplicity, quality and relatively low cost, all of which make it well suited to the property industry. It has supported the commoditization of energy efficiency performance between building owners and tenants, and between portfolios and shareholders. In sectors where such market-based motivators are absent, however, NABERS has been less successful and further work is required to achieve uptake and efficiency improvements. Government-led procurement requirements and mandatory disclosure appear to be the most obvious drivers that could improve performance in these sectors.