Many homes built before 2004 do not meet modern energy standards under the NSW Building Sustainability Index (BASIX). This affects the home’s comfort, energy use and emissions.
To help improve the energy efficiency and comfort of these homes, we commissioned a research project to collect data about their performance. We found many homes lacked basic features that kept residents comfortable, and targeted upgrades could significantly improve performance.
About the research
The NSW Department of Climate Change, Energy, the Environment and Water partnered with the University of Wollongong and Instinct and Reason on this Australian-first study. The study assessed 1,091 homes built before 2004. These homes were selected to represent common types of NSW houses.
Accredited energy assessors visited each home. They collected data on building materials, insulation, windows, fixed appliances and solar PV systems.
The results were analysed using a robust and statistically representative method. This created a clear picture of how older homes perform in real conditions.
What we found
The research confirmed our existing assumptions about the overall low energy performance of housing in NSW. We found:
- Many homes lack basic features that support thermal comfort and energy efficiency.
- The average rating was 2.1 NatHERS stars, well below the current 7-star standard for newly built homes
- These homes are harder to keep comfortable without heating and cooling. This leads to higher energy use and emissions.
- Targeted upgrades can significantly improve performance. For example, taking action to improve insulation, draught sealing, efficient heating and cooling, and windows can improve comfort and reduce energy use by up to 39%.
- There are 6 common types of older homes, with the most common (21%) being a detached brick veneer house with a timber floor.
Contact us
For more information about the project, email us at [email protected]