Every renovation and new build project is an opportunity to create positive environmental change. But where should we concentrate our efforts to achieve the greatest impact?

In today's episode, Dr. Paul Matthew, a lecturer and researcher at the University of Queensland School of Architecture, Design and Planning, will share his research on building for a changing climate to help guide us forward.

Today we'll learn about:

• The latest climate change science and what we need to focus on in design.
• The regulatory changes in the pipeline for existing and proposed houses to help tackle climate change,
• The key steps to achieve net zero carbon, and
• Loads of other valuable insights, and practical information from Paul's years of research.

MORE INFORMATION

Find everything you need on the Renovation Collaborative website.

www.renovationcollaborative.com.au

• PODCAST Key points summary, timestamps and resource links
• FREE RESOURCES Transcript edited into clear Q&A.
• CPD Australian architects can find more information on CPD, and
• COURSES Eleven easy to read courses demystifying the entire home design and construction process.

KEY POINTS SUMMARY

1. The CSIRO have modelled the potential future impacts of climate change over course of the century in all the Australian climate zones. The link to this CSIRO document is in the show notes.

As the climate warms, design to optimise cooling through cross ventilation in summer will be critical for the whole of Australian. However it’s essential that rooms to be mechanically heated or cooled can be efficiently insulated and sealed to minimise energy consumption.

2. The Australian Government is planning two significant building regulatory changes to tackle climate change.

• The first proposed change affects new building work – Embodied carbon calculations are required as part of the Australian National Construction Code approval process. This change was enacted in 2025 in NSW for commercial buildings only. However, the goal at this early stage is to establish a standardized method for measuring embodied carbon.
• The second proposed change is for existing houses - An operational energy assessment will be required at the point of sale or lease using the NatHERS tool. This change is yet to be enacted, but it's worth noting that a very similar scheme has been in place in the ACT for over 25 years.

The primary objective is to reduce operational carbon. To create highly energy efficient homes through strategies such as:

• climate responsive design
• systems like Passive House
• adding rooftop PV panels, and
• purchasing renewable energy via the grid

• maintaining and reusing existing buildings, rather than demolishing and rebuilding, and
• choosing lower embodied energy materials.

• looking at carbon offsets to balance out the remaining embodied and operational carbon. But be very careful where your offsets come from because they are not all legitimate.

5. A lifecycle assessment is a method of evaluating the environmental impacts of a building from the creation of its components, construction, operation and refurbishment to its ultimate deconstruction and disposal. It looks at a comprehensive range of environmental impacts. Lifecycle assessments are currently predominantly used for large-scale commercial projects but are equally valuable for houses.

6. Circular economy thinking is based on the concept of the closed-loop system. It involves designing to minimize waste and maximize resource efficiency by keeping materials in use for as long as possible.

There is a hierarchy of 10 broad R strategies. The objective is to stay up as high as possible. So rethinking and reducing is better than reusing or repairing, and reusing and repairing is better than recycling or recovering.

NOTE: These are the opinions of Dr Paul Matthew and he is not speaking on behalf of The University of Queensland

INTERVIEW QUESTIONS

[00:01:11] How did your passion for sustainable architecture begin?

[00:03:42] Please clarify the meaning of the term sustainable architecture?

[00:09:11] What are the current global predictions for climate change from the IPCC?

[00:10:47] What are the climate change scenarios forecast for Australia?

[00:13:23] How do the CSIRO climate change scenarios align with the Paris Agreement and Australia's commitment to net zero emissions by 2050?

[00:16:08] Can you tell us what NatHERS is and how it works?

[00:22:48] There are two building regulatory changes in the pipeline for Australia to tackle climate change - the first one is for existing houses and operational energy assessments at the point of sale or lease. Can you tell us about that?

[00:25:07] The second regulatory change in the pipeline is about calculating embodied carbon. Can you tell us about that?

[00:26:20] Can you explain net zero whole of life carbon?

[00:28:51] What should we focus on in design to work towards net zero whole of life carbon?

[00:36:43] Where's everything moving to with electric energy supply and use?

[00:40:00] Does choosing timber construction for carbon sequestration make a difference?

[00:46:17] What is a life cycle assessment?

[00:54:47] Are lifecycle assessments applicable for use on houses?

[00:57:08] What does Circularity mean?

[01:02:32] Key Points Summary

IN THE NEXT EPISODE

Next week, we continue exploring the latest science and delve further into the importance of regenerative design and circular economy thinking.

We’ll investigate the renovation and extension of a 150 year old timber cottage on a small suburban inner-city site in subtropical Brisbane.

I talk to architect, Andrew Noonan, director of Andrew Noonan Architect who will share the inside story on renovating his own home. Andrew extensively researched his design, product and material choices to ensure they optimised regenerative outcomes and he shares his very interesting findings.

RESOURCE LINKS

Environmental Performance in Construction database, University of Melbourne

The EPiC Database is a comprehensive and consistent open-access Life Cycle Inventory of environmental flow coefficients for construction materials, containing over 1 000 embodied emissions, energy and water coefficients.

CSIRO – Australian Climate Change Projections - https://www.csiro.au/en/research/environmental-impacts/climate-change/climate-change-information

Paris Agreement - https://unfccc.int/process-and-meetings/the-paris-agreement

Climate change graphics and information

https://globalcarbonatlas.org/budgets/carbon-budget/

https://www.ipcc.ch/report/ar5/wg1/summary-for-policymakers/

Australian National Construction Code

NatHERS https://www.nathers.gov.au/

Basix https://pp.planningportal.nsw.gov.au/development-and-assessment/basix

Think Step ANZ Report - ThinkStep ANZ – Embodied Carbon and embodied energy in Australia’s buildings

Articles about the problems with Carbon Offset Schemes

Financial Review Article (02.06.2025) Bad carbon credits are undermining climate progress

The Australia Institute (23.01.2024) Here are 23 times carbon offsets were found to be dodgy

The Australian Institute (23.02.2023) The problems with carbon credits and offsets explained

The Sydney Morning Herald (12.02.2025) Australians are being misled by ‘dodgy’ offsets, say Fortescue

The Guardian (19.01.2023) Revealed: more than 90% of rainforest carbon offsets by biggest certifier are worthless, analysis shows

GET IN TOUCH

If you've got any comments or questions or there's any topic you'd like to know more about, please send me an email at [email protected].