What is 7 Star?
The 7 Star standard in construction is a high-performance rating system that is part of the Nationwide House Energy Rating Scheme (NatHERS). NatHERS is a national framework that rates the energy efficiency of residential buildings, with ratings ranging from zero to ten stars. A 7 Star rating within this scheme shows that a new home has been constructed to the minimum standard for energy efficiency and will still need some mechanical heating and cooling to keep it comfortable to live in.
Key Features of a 7 Star Property
- Thermal Comfort: Homes with a seven-star rating provide better thermal comfort, meaning they keep a more consistent, comfortable indoor temperature all year round, with lower reliance on artificial heating and cooling.
- Insulation: These homes typically have better levels of insulation in walls, roofs, and floors, responding to the demands of different climate zones and reducing the need for heating in winter and cooling in summer. NatHERS has identified 69 climate zones, each with unique challenges, even within a 24-hour period.
- Glazing: Energy-efficient windows, for example double or triple glazing, are generally used to meet the needs of specific climate zones and minimise heat loss in winter and heat gain in summer.
- Orientation and Design: The design and orientation of the home take advantage of natural light and solar heat during winter and limit heat gain in summer, again this will vary depending on the impact of the climate zone. Thinking about where to place windows and shading devices is essential. Shading can be used to prevent overheating during summer and in hot climates; however, too much shading can have a negative effect during the winter or in cold climates.
- Building Materials: Using materials with good thermal properties is encouraged to enhance the home's overall energy performance.
- Ventilation: Proper ventilation systems are incorporated to ensure good indoor air quality and energy efficiency.
- Lower Energy Bills
- Environmental Impact
- Comfort
- Resale Value
Benefits of a 7 Star Home
- Lower Energy Bills: Energy costs are lower due to less energy consumption for heating and cooling.
- Environmental Impact: These homes have a smaller carbon footprint, contributing to reduced greenhouse gas emissions and helping to mitigate climate change.
- Comfort: Improved thermal comfort makes for a more pleasant living environment.
- Resale Value: Homes with higher energy ratings can potentially have higher resale values due to their efficiency and sustainability features.
Compliance and Certification
Achieving a 7 Star rating involves a detailed assessment using NatHERS-accredited software. This software simulates the home's energy usage, taking into account its design, materials, orientation and climate zone. Builders and designers work with accredited assessors to make sure that the design meets the rating criteria.
Context in National Policy
Unlike many parts of the world, Australian homes are getting bigger, and most people live in detached houses rather than apartments. This can lead to higher levels of energy consumption, and so making sure that these homes are energy efficient is even more important. Higher star ratings have become more common as Australia focuses on reducing carbon emissions and promoting sustainable living. Building code changes reflect overall plans to enhance the sustainability of residential construction and contribute to national energy efficiency targets. The 7 Star standard is key to this goal, reflecting Australia's commitment to better building practices and the environment.
From 2018 to 2022, new homes had to be designed to a minimum 6 Star energy rating under the NatHERs scheme. But state-based regulations meant that, in some states and territories, homes could be designed below six star. The move towards the 7 Star standard is part of a broader national strategy under the National Construction Code (NCC), which aims to improve buildings' energy efficiency. Changes to the NCC in 2022 now require all new homes across Australia, except in the Northern Territory and Tasmania, to achieve the equivalent of 7 Star NatHERS thermal performance.
The 7 Star implementation timeline varies; full enforcement depends on state and territory adoption and regulatory processes. While a 7 Star energy rating for new homes isn’t yet a reality for all of Australia, various states and territories have steadily increased the minimum energy efficiency requirements over time.
Current Minimum Standards (as of June 2024)
|
|
|---|---|
Victoria: | Since 1 May 2024, Victoria requires a minimum 7 Star rating. |
New South Wales (NSW): | NSW now requires a minimum of a 7 Star energy rating for new residential buildings. |
Australian Capital Territory (ACT) | Since 15 January 2024, all new homes must reach a minimum of seven star. |
South Australia: | Like other states, South Australia requires a minimum six-star rating. From 1 October 2024, all newly built homes in South Australia must meet a 7 Star energy rating. |
Queensland: | New houses and townhouses must now achieve a minimum 7 Star energy equivalence rating in Queensland. |
Western Australia: | New homes must achieve a 7 Star rating from 1 October 2025. |
Tasmania: | New homes, extensions and additions to existing homes must meet the 6 Star requirement in Tasmania. It is delaying considering the compulsory 7 Star energy efficiency rating until the next version of the National Construction Code (NCC) in 2025. |
Northern Territory: | NT aligns with the 6 Star minimum requirement. |
Factors Influencing 7 Star Adoption
Clearly, 7 Star isn’t yet mandatory nationwide, so why not? The reasons fall into three categories:
- Regulatory Framework: Adopting higher standards requires updates to state and territory legislation and regulations. The National Construction Code (NCC) sets the baseline, but states and territories must adopt and enforce these changes.
- Industry Readiness: Builders and developers need time to adapt to new requirements, as well as training and resources to understand and implement the new standards. This includes familiarisation with new materials, construction techniques and compliance procedures. The construction industry has to adapt to changes in design practices, ensuring homes meet higher efficiency standards without significantly increasing costs. The supply chain must also meet increased demand for energy-efficient materials and technologies, such as advanced insulation, energy-efficient windows and renewable energy systems.
- Market Conditions: Economic factors and market readiness can influence the pace at which higher standards become compulsory. As consumer demand for sustainable and energy-efficient homes grows, the market naturally shifts towards higher standards. Real estate trends show a growing preference for eco-friendly homes, which can influence builders to adopt higher standards even before they become mandatory.
Looking Ahead
It's crucial to stay updated with the latest information from local building authorities or the Australian Building Codes Board (ABCB) as regulations are subject to change. Being proactive ensures you know any new requirements or standards that may affect your construction projects. Current progress suggests that higher standards, including the 7 Star rating, will become mandatory across more states as part of national efforts to improve the building sector's energy efficiency and reduce carbon emissions.
Overall, the 7 Star standard demonstrates a home's energy efficiency and sustainability, representing Australia's commitment to better building practices and environmental stewardship. For up-to-date information and tips for achieving seven star, visit official state government websites or the ABCB website.
