The NSW Government is showing a strong commitment to the development of sustainable and resilient homes and buildings. A new State Environmental Planning Policy (Sustainable Buildings) 2022 looks to encourage the design and delivery of more sustainable buildings across NSW. It sets sustainability standards for residential and non-residential development and starts the process of measuring and reporting on the embodied emissions of construction materials.
The purpose of the new SEPP is to:
- minimise the consumption of energy and potable water
- reduce greenhouse gas emissions from energy use
- monitor the embodied emissions of building materials
- deliver buildings that are comfortable in summer and winter
The SEPP will bring changes that ensure the buildings we live and work in are more comfortable places to be. It is hoped that the thermal performance measures will mean that buildings are cooler in summer and warmer in winter, making homes and offices more energy efficient and ultimately cheaper to run.
Building Sustainability Index (BASIX) standards
Since 2004, more than 500,000 BASIX-compliant homes are reckoned to have saved 12.3 million tonnes of greenhouse gas emissions, and 340 billion litres of drinking water. The NSW Government will be Increasing the BASIX standards to improve the performance of homes with key changes to existing sustainability standards for new residential buildings:
- an increase of the thermal performance standard from an average of 5.5-6 stars to 7 stars NaTHERS rating (Nationwide House Energy Rating Scheme)
- an increase of between 7-11% in greenhouse gas reduction (varies depending on location and type of residential development proposed)
The BASIX standards are complementary and consistent with those proposed in NCC 2022.
Provisions for non-residential development
The sustainability provisions for non-residential development are new and will include:
- embodied emission measurement and reporting for all developments
- energy standards for large commercial developments, with energy performance to be verified after the buildings are occupied and offsets purchased for residual emissions
- minimum water standards for large commercial developments
- certain developments to be ‘all electric’ or capable of converting to operate without fossil fuels by 2035
What else could be utilised to improve building sustainability?
Australia’s build-to-rent market has grown massively in recent years as rental demand and prices have soared. While developers race to build more apartments, extreme weather events have sparked mould issues which, along with Covid-19, have brought concerns about proper ventilation in buildings. Furthermore, supply chain problems and labour shortages continually threaten project timelines and businesses across all sectors. Could a set of sustainable building guidelines from Germany be the answer to developers’ prayers?
Using a scientific approach, Passivhaus (passive house) sets out how to design a building to significantly reduce heating and cooling costs and increase thermal efficiency and comfort. The principles include continuous insulation, no thermal bridging, air tightness, mechanical ventilation and heat recovery, and insulation of all components. Integration and consideration of all aspects of every stage is key in a passive house development as a means of designing a building to achieve net zero emissions.
With this approach showing the way, it is possible for legislators to ‘encourage’ architects and developers to adopt sustainable practices which will benefit the planet with anticipated results looking to further reduce greenhouse gas emissions by around 2.6 million tonnes over the next 10 years (equivalent to planting over 8 million trees or running 54 wind turbines for 10 years), helping NSW on the path towards net zero.
What happens next?
The Sustainable Buildings SEPP and Regulation amendments will commence on 1st October 2023 to give industry and assessors time to be ready. Savings and transitional provisions have been included so that the SEPP will not apply to development applications or modification applications that have already been submitted, but not yet determined by the commencement date. The development standards within the SEPP will be reviewed in 2025 and then again, every three years.
It should be noted that the biggest opportunities for growth of the passive house approach by sector have been identified as single dwelling residential, public and social housing, residential and commercial multi-storey, education, build-to-rent and healthcare. In other words, there will not be many development types left untouched by the drive for sustainable living and working built environments.