In a trifecta of residential energy efficiency announcements this week, changes appear to be coming thick and fast.
As well as proposed updates to the National Construction Code (NCC), The Nationwide House Energy Rating Scheme (NatHERS) is now offering voluntary assessments for existing homes based on the Victorian model, and the Green Building Council of Australia (GBCA) released its new certification standard for industry uptake.
Energy efficiency updates to NCC open for feedback
Under a significant overhaul to the 2022 NCC, one of the changes being considered is increasing thermal performance requirements for homes from the current, 6-stars NatHERS equivalent, to an equivalent of 7 stars.
Other proposed changes include:
- introducing whole-of-home annual energy use requirements (noting differences between different building types) flagged in our News from the Front Desk last week
- a new set of Deemed-to-Satisfy elemental provisions for apartments
- new provisions designed to allow easy retrofit of on-site renewables and electric vehicle charging equipment for properties not including houses
- enhanced condensation management provisions, including additional ventilation and wall vapour permeability requirements
The NCC draft changes will remain open for public submissions until 17 October.
It is the second round of feedback on the next iteration of the NCC, which is updated every three years, with stage one of public consultation closing in early July.
Changes covered in the first round included the introduction of accessibility requirements for all new homes, such as creating wider doors and passageways, making bathrooms wide enough to accommodate walking aids, and having bathroom walls structurally sound enough to hold mobility aids.
NatHERS adopts energy efficiency program for existing homes
NatHERS new National Scorecard Initiative, which builds on the Victoria’s state-based Residential Efficiency Scorecard Program, is a voluntary thermal performance and energy efficiency assessment now available nationally to existing homes.
Accredited assessors provide a star rating and detailed certificate to the household as well as advice on opportunities for improvement, with the cost of an assessment typically ranging from $250 to $500.
Assessments are based on the performance of the home in hot and cold weather extremes and the energy used by major fixed appliances such as air conditioners, heaters and hot water systems.
“The NatHERS endorsed National Scorecard means every home can now be rated to show energy cost, comfort and greenhouse gas emissions – and what we can measure, we can more easily improve,” Victorian minister for energy, environment and climate change Lily D’Ambrosio said.
It will take time to mesh the new initiatives with NatHERS existing suite of assessors and processes. Current NatHERS methods are primarily used to assess new homes based on plans and building specifications, which are often not available for existing homes.
The National Scorecard Initiative is expected to be fully accredited and phased into NatHERS in 2022. Until then all elements of the new scorecard, including the assessment tool, assessor training and accreditation, will continue to be delivered by the Victorian Government on behalf of all Australian governments.
GBCA releases new residential certification standard to industry
The GBCA is calling on the volume home building industry to adopt its Green Star Homes Standard certification system now, ahead of a planned consumer release in 2022.
The new standard sets a high benchmark, requiring homes to not only be well ventilated and insulated, water and energy efficient and climate change resilient, but also fully electric and powered by renewables.
“The Green Star Homes Standard is a game-changer that will bring more liveable, marketable, climate positive new homes within reach of everyday Australians,” GBCA chief executive Davina Rooney said.
“Green Star certified homes will reduce a household’s energy costs by over 75 per cent, through things like solar panels, better insulation, smarter air conditioning, LED lights and electric appliances.”
Already on board to trial the standard are 11 industry stakeholders including Stockland and Metricon, with the aim of seeing costs fall across the marketplace as scale increases.
Andrew Whitson, Stockland group executive and chief executive communities, said his company would deliver its first Green Star Home at Stockland Waterlea in East Melbourne.
“There’s never been a more important time to be launching this. We’ve seen customer preferences change and accelerate,” he said.
“People are going to work more from home now, so is the home set up to do that? Is it a low energy environment? Is it resilient and healthy? These things will go from a ‘nice to have’ to a ‘must have’.”
According to Ms Rooney, The Green Star certification will be equivalent to 7 or 7.5 star NatHERS rating, depending on the climate.
Action on residential energy efficiency a welcome change
The incoming tide of changes have been broadly welcomed, with most in the industry acknowledging the need to greatly improve the energy efficiency of Australia’s building stock, particularly in the residential space.
According to RMIT University sustainable housing expert Dr Trivess Moore, increasing efficiency standards from 6 to 7 stars across Australia would reduce the amount of energy required for heating and cooling by 24 per cent.
“The performance of new Australian housing is at least 40 per cent worse than many other developed countries in similar climate zones,” Dr Moore explained.
According to Dr Moore, four out of five new homes were still being built to the bare minimum standard, meaning consumers and society were missing out on the benefits of an “economically optimal” rating of 7.5 or above.
He also pointed out there was frequently a discrepancy between design and actual performance outcomes, raising the need for better oversight and accountability to accompany any regulatory changes.
Research by the Australian Sustainable Built Environment Council (ASBEC), estimated delaying the changes by just three more years until 2025 could cost homeowners an additional $2 billion and lock in nine million tonnes of emissions between now and 2030.
ASBEC interim executive director Alison Scotland said, “If we are serious about reducing emissions, saving money and increasing resilience of our buildings, we need to continue the momentum towards stronger energy performance — and this 2022 step change for residential buildings is an important part of the process.”