Mr Michael Ambrose

Michael joined CSIRO in 1992 and is a senior experimental scientist in CSIRO’s Land and Water. He leads projects for industry and the Australian government, involving building energy efficiency, life cycle analysis and sustainable urban development.

Michael is currently undertaking analysis of house energy rating data obtained from the Universal Certificates (UC) that are created as part of the NatHERS energy efficiency compliance requirements for new houses contained within the National Construction Code.   Over 350,000 UC’s are in the database and this is allowing unprecedented insight into how new house designs are achieving their energy efficiency requirements.  As part of this work Michael is creating interactive data visualisation dashboards that will allow users to explore the data geospatially to discover area specific trends and practices.

Recently completed projects include assessing data gathered as part of the Low Income Energy Efficiency Project that was done in collaboration with the South East Councils Climate Change Alliance and leading the investigation into air infiltration rates of newly constructed houses across Australia.  This ground breaking research was the first time a major study of infiltration rates had been undertaken in Australia.  Around 140 houses were tested and analysed and the research results has led to changes in how residential buildings are accessed for compliance with the National Construction Code.

Michael is the author of numerous book chapters, papers and reports on building energy efficiency and urban sustainability.

INTERACTIVE ROUNDTABLE: Are we there yet? Is the 6 star thermal rating good enough and should we now focus on other aspects to improve dwelling energy efficiency?

As part of the recently endorsed Trajectory for Low Energy Homes project was the Report for Achieving Low Energy Homes.

It included recommendations that for the 2022 revision of the NCC there should be an aim to:

• Introduce an energy (and carbon) usage budget that includes appliances already covered by the NCC (hot water, pool pumps, and lighting), adds a new requirement for space conditioning, and increases thermal efficiency requirements up to 7 stars equivalent in some climates;
• Ensure homes are ‘ready’ to accommodate on-site renewable energy generation, storage and electric vehicles;
• Introduce whole-of-home tools and a simple elemental pathway to verify compliance;
• Consider opportunities for building sealing, while addressing any ventilation and condensation impacts;

While many welcomed this trajectory, some in the housing industry did not. The Housing Industry Association (HIA) in a submission to the draft report stated that “HIA is extremely disappointed with the recommendations proposed in the draft report, … which just targeted the building fabric and the blunt ‘star-rating’ approach as opposed to a holistic approach that considered building use and overall energy efficiency performance.”  The HIA also stated that they believed that “there would be far greater gains to be had by tackling energy efficiency upgrades for existing housing stock rather than seeking to further increase standards for our already highly efficient housing stock built to current 6-star standards.”

This roundtable asks is the HIA right? Is the current required thermal efficiency of the building envelope good enough and should we instead focus on other aspects such as appliances and PV systems or alternatively should we focus our attention on the existing housing stock and improve that and not worry about improving our new builds any further?  Some of the questions to consider:

• Is a 6 star rated building highly efficient and if not what star rating is?
• Is the NatHERS system a blunt tool and if so how could it be improved or is a totally new approach needed?
• Is a holistic approach to building energy use the right way to go and if so, what should be included?
• Should we now focus on existing housing stock and if so how?
• Are our new homes good enough in terms of energy efficiency and if not, where can they be improved?