The requirements a new home will have to meet in order to achieve Green Star certification are taking shape with the release yesterday of a draft Green Star Homes Standard for consultation.
Part of the Green Building Council of Australia’s Future Homes Strategy, the Standard is a key tool to help drive transformation in the residential sector to create a market for healthier, more resilient, energy efficient homes.
Green Building Council of Australia (GBCA) CEO, Davina Rooney, said the Standard will lift the bar on current regulatory settings and proposes an ambitious suite of minimum criteria.
“To achieve Green Star certification, as a minimum, homes will need double glazed windows and doors, air filtration and LED lighting, good access to daylight in living areas and bedrooms, sufficient renewable energy generation to support the home’s operations and no fossil fuel use,” Rooney said.
The Standard is being developed collaboratively with rigorous consultation and input from industry, consumers, builders, banks, investors and insurers to ensure it is fit for purpose.
To achieve widespread change at scale, the Standard is primarily targeted at volume home builders and large-scale residential developers, from whom it has already received strong support.
Stockland, Mirvac, Metricon and Rawson Homes, along with Chatham Homes, Passive House, Landcom and Development Victoria have all committed to piloting the new draft Standard through the early access program.
The Standard enables builders to seek certification for an entire standard home product line as Green Star Designed. Built homes that have been tested and are compliant with the requirements of the Standard can be Green Star Certified.
Rooney said the Standard is focused on delivering health benefits to residents as well as future-proofing Australia’s residential sector.
“Working in partnership with builders, financiers and investors we want to help ensure the next generation of Australian homes are built to better withstand natural disasters, cope with a changing climate and lessen the built environment’s contribution to emissions,” she said.
“By significantly lifting the standard to which new homes are designed and built we can dramatically improve health and wellbeing while at the same time lowering energy bills and helping to meet our emissions reduction commitments.
“Drought, bushfires and now the coronavirus pandemic have all underscored how vital it is to have more resilient housing that better protects the health of residents and the planet.”
Stockland Group executive and CEO Communities, Andrew Whitson, said that as Australia’s largest residential developer, the company is passionate about creating liveable, connected and sustainable communities across the country.
“We are delighted to be partnering with the Green Building Council to deliver one of the first new Green Star Homes in the country as part of the Early Access program,” Wilson said. “This program will make an important contribution to the delivery of sustainable new homes now and into the future.”
Green Star Homes will be a national standard that assesses and certifies a home. It applies the demonstrated success Green Star certification has achieved in other sectors such as office, retail and industrial to residential.
For example, Green Star-rated office buildings not only provide a healthier environment for workers, they also deliver a clear ‘green premium’ at the time of sale, higher net incomes and significantly lower vacancy rates.
Achieving Green Star Homes certification will require applicants to meet a range of criteria across three primary categories.
Firstly, Green Star Certified homes will need to be well ventilated to prevent the growth of mould and built to minimise the entry of pollutants, such as bushfire smoke. They will need to be thermally comfortable, use materials that are low or non-toxic and have high quality lighting installed.
Secondly, they must be resilient. Catastrophic events such as the recent bushfires in 2019 highlight the need to improve resilience standards in the design and construction of new homes.
In Australia, extreme heat kills more people than any other natural disaster. Urban areas, particularly areas with reduced vegetation cover and a lot of hard surfaces absorb, store then radiate heat, leading to the urban heat island effect.
Green Star Certified homes will need to be built with proactive measures to be better than Code at withstanding natural disasters and future climate change conditions such as bushfires, flooding, and heat stress.
The draft Standard proposes that a Green Star Certified home achieve a 40 per cent reduction in water usage when compared against a reference home with measures such as landscaping to mitigate heat stress.
Data shows that 57 per cent of Australia’s total built environment emissions come from our homes and on average across Australia, most energy (40%) is used to heat and cool homes, with the majority going to the heating of homes during winter.
The third criteria is for Green Star Certified homes to be net zero. This means that they have been built to generate sufficient renewable energy to power all estimated regulated loads as well as estimated appliances and plug loads.
They do not use gas, major appliances including refrigerators, washing machines and dishwashers must have a minimum 4-star energy efficiency rating, solar systems must be battery ready and all windows must be factory built double glazed IGU (Insulated Glass Units).
Airtightness is a key criterion with more than 25% of heat loss in winter estimated to be caused by draughts. Good insulation when combined with airtightness can save homes up to 40% in energy bills every year.
“With our population set to continue growing to 31 million people by 2030, we will need to build an extra 197,000 new homes every year to meet demand,” Rooney said.
“Australians are already feeling the worsening impacts of natural disasters and paying among the world’s highest energy bills, so we must act now to ensure this pipeline of new homes is built to higher sustainability standards.”
Consultation on the draft standard will run until October 30, 2020. A copy of the Green Star Homes Draft Standard and information on how to provide feedback is available here https://new.gbca.org.au/rate/green-star-strategy/green-star-homes/