On what happened at Carbon Triggers

We usually get some good swings on the voting at our debates – held before and after the panel speaks and the audience lets fly at the QandA  questions, comments and answers. The dial tends to move the way we thought it would. Or want it to!

But not this time. There was a hair’s breadth difference in the yes vote to support the proposition that we need to mandate carbon budgets to prevent demolishing existing buildings.

What was interesting was the big swing towards the “don’t know” pod.

An indication that this is a very complex issue.

To be honest as we interviewed people ahead of the debate, we found the topic indeed becoming more complex and nuanced.

Among some of the sit up straight moments was Tristram Carfrae’s view that the proposition was false. 

 “I’ll start by saying I’m not sure I agree with the mandate. I’m not sure we need to stop demolishing all buildings, and I’m not sure we should wait for any government regulation to do what we should be doing,” said this highly regarded Arup engineer.

We should instead be creating a “better built environment, design and build it better for people, better for nature, and better economically,” he said. “And the second one, of course, is to reduce our carbon emissions while we do so.”

The next obvious thing to do is build less and build smaller – a call that resonated across many people in the audience and on stage.

Slashing carbon is not so hard, Carfrae said.

“I can safely say, hand on heart, I can take 50 per cent of the material out any typical building.”

There’s retrofitting, re-using existing materials. There’s rethinking grids or the way floor plates are laid out. “Australia has an addiction to ridiculously long spans. They cost both money and carbon.”

And basements for bicycles? Not a good idea. And transfer structure should “just be immoral”, he challenged.

But forget mandates, he said. It takes too long to get such political support for such moves. In the networking after the event someone made mention of the enormous support to stop gambling advertising and yet the government will not move to enforce a ban, as a case in point that politics can badly lag general sentiment.

But we look to things like cars as an analogy – producers or consumers are not expected to make the right choices on elements such as seat belts and safety. These are mandated because they’re too important to leave to the market.

A burning planet and carbon emissions are likewise critical issues on which in our view the market is incapable of making a rational choice because it’s focused on short term cost. (Car manufacturers fiercely objected to mandatory seat belts when they were introduced – their businesses would be destroyed they said.)

The UK has mandated carbon assessments through the London Plan, but what Carfrae pointed out was that this originated in the market via a group of about 1000 professionals that included real estate agents wanting better standards in buildings.

The thing about constraints we thought is that they drive creative responses and innovation.

Deputy Lord Mayor of Sydney Jess Miller kicked off her session with some of her typical challenges and provocations. Was it a “man date” we were seeking, she asked, or a “lady date”?

The first was likely to be very structured and orderly, the second contained a “level of excitement, flexibility, compromise. Sometimes a little bit of indecision, but ultimately, lady dates are very good at being site specific, and I think that’s where we’ve got to get to on this.”

Given her position as a politician Miller was in the business of trade-offs, compromise, “and avoiding the city being sacked or having what little planning rules we have remaining taken from us.

“So let’s be pragmatic. I think if the rules are too rigid, the state comes in. Everything will become state significant”.

Some buildings require too much work to retain, noting those slated for demolition to make way for Town Hall Square, for instance.

Architect Filomena Beshara from Freecity said that as she was now a developer she wanted to point out that she agreed with the notion that we should consider embodied carbon when looking at new projects, “but we should be really, really careful about the way we do it” especially if this was included in a contractual obligation since two measurements by different people can produce completely different results.

Developers already strive to be creative and will use “skinny” slabs and efficient facades wherever possible. “They want to save money and they want to do things more efficiently”

And then there was the question of who pays?

Jeff Morgan of Hassell said that a case could be made for both sides of the debate. During his work to assist MECLA an organisation that strives to create market momentum for low carbon materials, a key objective was to influence the broader construction industry.

But did it work?

“We were all very conscious that the projects we were talking about, working on – industry leading – actually represented just a really small proportion of the projects built across the entire country.”

He noted Stockland’s decision to upgrade Picadilly Centre in Sydney rather than redevelop it.

But to make the change that’s truly needed, “everyone in all buildings really need to address this in some way…We really can’t rely just on these sort of flagship projects here or there”.

Michael Mihailou said quantity surveyors knew that clients needed certainty. It was possible to price up four or five options for the way projects could be built but if carbon mandates come into play it could add to difficulties and cost pressures.

However, there are also opportunities to reduce carbon and along with it – cost – the two tend to work together. Removing a balcony for instance and replacing it with a Juliet balcony could save $20,000.

Jillian Hopkins said heritage and older buildings add “grit and grain to our city and make great places to live and to visit, so I think we need to take a more expansive view when we consider the economics of keeping old buildings”.

The first step to realising a carbon budget is to ensure consistent metrics to measure embodied carbon, Hopkins said.

In October 2023, NSW Government released the Sustainable Buildings SEPP, which mandates that all commercial, non-residential buildings of a certain scale need to report on their embodied carbon with their planning application.

In 2024, NSW Treasury released the Carbon emissions in the investment framework, which is a way for the NSW Government to measure carbon impacts in our own projects at the business case stage.

Hopkins said that government can and does lead by example in retrofitting existing buildings or using low carbon products like green concrete. She mentioned the Central Station rejuvenation, Eveleigh Carriageworks and the recently completed Lands by Capella as examples of projects that have revived old buildings.  

When Maria Atkinson opened the room for engagement questions and comment flew quickly from an engaged audience poised on theatre style seating – creating an interesting dynamic for participation, we noted.

Nicole Sullivan, Thinkstep ANZ: “I think language really matters. We’re starting to move the concept of end of life to end of use when we’re talking about resources … I hate the word demolition, I think of a wrecking ball when I think of demolition, and I think of all those resources going to waste. What’s it going to take for us to change the word demolition to deconstruction when I see a spanner or a rattle gun instead of a wrecking ball?”

Filomena Beshara: “I try to deconstruct buildings instead of demolish buildings. It’s bloody hard but it doesn’t mean that shouldn’t be done. That’s the reason why we are here in this room.” This was a challenge that would need a completely new skill set, plus, ideally, a universal inventory of materials, and “coming from someone who’s trying to source materials for small projects, big projects, second-hand materials – it is a mess.”
“it’s really really hard.”

Tristram Carfrae: “we’re underestimating the issue” and it’s “very complex”.

While there were sometimes opportunities to reuse materials from one site for reconstruction, there still needs to be “a meanwhile factory to reassemble the material into panels or something usable for reconstruction.” Arup is working on how to do this with the Marks and Spencer building in Oxford Street, London, which is to be demolished, but it was early days.

“We’re doing research projects around it. Nobody’s actually got their teeth into the reality of what it actually means to deconstruct a building, truck it off site, reassemble a component, bring it back to site.”

Jeff Morgan: Demolition is a modern behaviour, he said and in the past people didn’t pay a demolition contractor to knock down a building and take away the rubble. “Someone would come…they would take the building apart, take away the door frames, window frames, take away the bricks, and they would make their money from the on selling of that.”

We need to “unlearn” some things in the way we build.

Reid Butler sustainable design leader at Hassell said in a welcome note at the start of the event that architects can build things that need a lot of carbon, “but we can also build things that can give back and regenerate and be beneficial to society today and into the future.”

“We have a bunch of frameworks. We have guidelines. We have principles. We have experts. We have a whole super great team, but we can’t do it by ourselves. So, we like to collaborate. We like to learn from people, and we like to share our knowledge. So that’s why we’re having this wonderful event here today.”