Can we Decarbonise Construction?

Richard Palmer, Director of Sustainability at Integral Group championing innovative thinking at the Green Building Council of South Africa’s (GBCSA), Green Building Convention 2021, in November 2021. Image is courtesy of GBCSA.

Pedraic Murphy

Associate Director
BG&E Perth

Daksh Baweja

Director – Specialists

BG&E Sydney

+61 2 9770 3300
Science indicates this decade will determine the long lasting impacts of climate change on our planet.

While 31 October to 12 November 2021, saw more than 100 heads of government come together at the United Nations’ Climate Change Conference of the Parties (COP26) in Glasgow, to discuss how to halve global emissions by 2030 – it is already clear that there is an immediate need to reimagine urbanism and the built environment – as it is responsible for approximately 75 per cent of annual global Green House Gas Emissions (GHG).

Richard Palmer, Director of Sustainability at Integral Group, who has 17 years’ experience as a senior engineer, TED speaker and world-class thought leader on sustainability, suggested that industries have framed sustainability objectives as “progress not perfection”, with marginal improvements being acceptable.

Richard says, “In 2015, everything changed with The Paris Agreement (a legally binding international treaty on climate change), when 196 parties agreed to develop emissions trajectories that would limit global warming to 1.5 degrees Celsius.”

While some emission-heavy sectors recognise the magnitude of the environmental crisis, the pace of action and mitigation remains steady in some nations and halted in others, based on the unanswered question of responsibility – is it government or the private sector, who are best placed to lead climate change action and/or bear the burden and costs, or is it both?

This issue resonates with many in the Property and Infrastructure sectors, as project stakeholders can’t always agree on the value of implementing sustainability measures in the design phase of projects.

One source suggested, funding was blocked for a project, as a stakeholder believed the financial gains of embedding sustainability measures in the design phase, would only see others reap the benefits later in the lifecycle of the asset, therefore providing no immediate value proposition.

Richard says, “Ordinarily governments are the more risk-averse, however when it comes to sustainability, there is a tangible argument that the public sector is better placed to lead, than the private sector. Particularly, because industry have to be realistic about balancing environmental commitments, client obligations and delivering shareholder value.”

While debate continues about which sector(s) should take the lead, it is undeniable that a united front would be the most effective approach to fulfil a long-term global solution.

The World Green Building Council’s (WGBC), Beyond Buildings 2021 Report, of which Richard is a contributor, calls for the Property and Infrastructure sectors to work with policy makers, to achieve a cohesive solution to the climate crisis.

The time has come for blue sky thinking and solution-focussed action, particularly when global leaders such as Bill Gates remind us that in October 2019, it was predicted that the equivalent of an entire New York City will be built every month, globally until 2060.

Richard adds, “Turning back towards what is considered as ‘the lucky country’, imagine an Australia where the natural landscape and biodiversity was conserved, with regional areas protected and restored, to help balance the increasing densification in cities?”

As the circular economy gains momentum by providing a model that unites the interdependencies between society, the environment and the economy – several governments, industry giants, project financiers, and asset owners and operators, are realising the benefits.

Bloomberg have forecast the value of global sustainable assets to skyrocket to $50 trillion by 2025, if we proceed with a 15 per cent annual growth rate, which is only half the annual growth rate from 2015 to 2020. Other benefits include improved security in the supply of natural resources and employment creation. Global circularity is about improving our liveability by reducing energy, resources and waste, as well as by increasing carbon efficiency. It includes recycling, sharing, regeneration and adaptive re-use when designing and delivering future assets.

Policies targeting a climate neutral circular economy by 2050, include Ireland’s Waste Action Plan For A Circular Economy 2020-2025, the European Green Deal 2019 and the European Union Circular Economy Plan 2020. It is predicted that Europe’s adoption of ambitious circular economy initiatives will increase Gross Domestic Product (GDP) by 0.5 per cent by 2030 and will create up to 700,000 new jobs.

Richard asks, “What would the urban economy become if we had to re-use materials and one building had to come down in order to build another? Unfortunately, that scenario is too much of a stretch for most to digest but stretching is needed. We have begun this journey by storing, using and reusing materials in a circular way. There’s an overwhelming opportunity to keep innovating and taking steps to solve the climate crisis.”

As noted by many including the Royal Academy of Engineering in the United Kingdom (UK), the role of engineers to help clients decarbonise the Property and Infrastructure sectors is the key to creating built environments for the next generation and beyond.

How do we Measure Decarbonisation?

The late British Scientist, Lord Kelvin said, “If you cannot measure it, you cannot improve it.”

By 2020, more than 3.5 billion square metres of green building space had been certified by the WGBC. This was predicated years prior when methodologies and benchmarks were implemented to help stakeholders achieve this outcome.

Similarly, it is promising that Main Roads Western Australian (WA) mandated the application of the Infrastructure Sustainability Council’s (IS Council), IS Rating Scheme, for projects over $100 million, according to Padraic Murphy, Associate Director – WA at BG&E.

The IS Council is a member-based, industry body operating in Australia and New Zealand to help enable enhanced sustainability outcomes in infrastructure.

Padraic is a Registered Assessor for the IS Council and says, “When it comes to sustainability, the writing is on the wall, it is the future, for all of us.

”While serving as the Service Delivery Manager for the planning and development phase of the Bunbury Outer Ring Road (BORR) in Perth in WA, Padraic observed the expanded role of the asset owner which derived significantly improved outcomes when applying the coveted IS Council’s Rating Scheme.

Padraic says, “Our client demonstrated considerable leadership on BORR, specifically in relation to working in partnership with the entire project team, which included GHD. We collectively developed a framework to ensure opportunities were incorporated to achieve robust sustainable outcomes, from project inception.

“The IS Council’s Rating Scheme helps technical experts to consider how we can benchmark the impacts of challenging conventional wisdom and pioneer something better, to deliver improved sustainability outcomes.”

While the IS Council’s Rating Scheme and similar instruments, such as the Green Star Rating Scale for buildings and the BREEAM Sustainability Assessment for master planning projects, infrastructure and buildings, are making inroads in the global Property and Infrastructure sectors, there are opportunities to leverage best-practice benchmarking tools from countries that are leading the charge.

Kye Taylor, Regional Manager – UK at BG&E says, “The sustainability landscape in Australia is where the UK was five years ago and that should be seen as opportunistic, not negative. The UK is helping clients in the Property and Infrastructure sectors to propel the planet’s sustainability initiatives forward and realise tangible outcomes for communities.”

Part of the UK’s success is attributable to client motivations, with many developers unable to secure funding unless projects are designed and delivered sustainably. Tenants and pension funds have also stepped up, by demanding net zero or low carbon assets.

During the last few decades, considerable gains have been made in reducing operational carbon, however in more recent times, the focus has shifted towards reducing embodied carbon and drawing on guidance from networks such as the London Energy Transformation Initiative (LETI), to help transition the built environment to achieve a net zero carbon future.

Kye says, “I strive to help our clients fulfil their obligations by reducing the embodied carbon on some projects by up to 55 per cent. We explore the various stages of design and specification, selection and supply of materials, manufacturing and transportation of materials, construction methods and assessing re-use possibilities.

“Large developers often talk about “carbon per square metre” on projects, for specific stages, as it helps to achieve higher sustainability standards for the entire project on delivery. It’s a very exciting time to be working in this field.”

Sharper Focus on Design, Regeneration, Materials, Construction and Procurement

Australia, among other countries, has an opportunity to learn from the UK and place a greater emphasis on design and specification, and the overall environmental impact of structural assets, in proportion to consideration of materials, believes Dr Daksh Baweja, Director of Materials at BG&E.

Daksh is also an Industry Fellow at the School of Civil and Environmental Engineering at the University of Technology in Sydney, a widely-published author of technical papers on the durability of fly ash and other concretes, and has held executive roles at CSR, Readymix and Rinker, among others.

He says, “There is an overwhelming opportunity for Australia to reassess what is happening in design and construction. An opportunity to pivot the focus away from popular methods of reducing embodied carbon by materials selection/use in isolation and broaden thinking towards innovative design and clever engineering. This should, be coupled with using the most advanced materials, which may at times, be a combination of conventional and unconventional. But we cannot continue to ignore the engineering when assessing sustainability.”

The abovementioned broader focus is being adopted by BG&E’s London team, across many projects, they also applying a sharper focus to regeneration and upcycling of existing assets. A live example from the UK is redevelopment of the Renaissance Hotel. BG&E is working with the Property Alliance Group on this best-practice example of upcycling, as part of the $320 million regeneration of the Deansgate site in Manchester’s city centre. The new hotel tower will be built around the existing core, reducing the need for demolition and generating an embodied carbon saving of around 2,760-3,800 tonnes.

In Australia, upcycling is also gaining traction, with the iconic Quay Quarter Tower (QQT) in Sydney. The tower is an asset developed, owned and managed by AMP Capital on behalf of its investors. The building from circa 1970 with panoramic Sydney harbour views has been transformed, almost doubling its floor space, yet retaining over 60 per cent of the core as part of the developer/owner’s sustainability commitments. BG&E worked closely with construction partner, Multiplex and others, to deliver the bold transformative vision for this landmark 49-storey uilding which was designed by 3XN of Denmark and is set to become one of the world’s great innovative workplaces. It is situated in a contemporary neighbourhood, with an expansive podium, over one acre of green space and extensive retail amenity for tenants and visitors over two city blocks.

The sheer scale and complexity of the development vision, design, structural engineering, monitoring, materials testing and simultaneous programmes of work to demolish, renovate and build, makes QQT an exceptional engineering feat, as well as a shining example of a truly sustainable structure and forward-thinking development vision.

While upcycling is an effective sustainable design option, Daksh also advocates achieving structural efficiency is key, as it provides rewards in terms of efficient and sustainable design and materials use, which is highly valued by some industry leaders wanting to implement projects cheaper and faster.

The Evolution of Concrete and Other Materials

Concrete is consumed at a rate of 33 billion tonnes per annum and is the most commonly consumed material in the world after water. This rate of use has sparked environmental concerns regarding concrete’s extensive manufacture and depletion of raw materials, with an emphasis on the impact of cement use. Contributing seven-to-eight per cent of the world’s manmade carbon dioxide, the global cement industry would be the third largest emitter of GHG, if it was a country.

Supplementary cementitious materials (SCMs), such as fly ash and slag, have been used in construction for over 40 years. In Australia alone, the use of SCMs has reduced embodied carbon by 30-35 per cent, relative to the use of cement. However, reduction of cement can make it more difficult to achieve concrete structural efficiency and durability, for commonly nominated asset design lives of 50-100 years.

Daksh works with SmartCrete, one of Australia’s Cooperative Research Centres (CRC) focussing on concrete. The Centre promotes scientific and engineering research for the concrete industry, including developments within the concrete supply chain and associated industries, with matched government funding for projects.

He says, “Cement is the most expensive thing to put into concrete and if there was a way to reduce it in concrete, it would have already been embraced by industry for economic reasons. Therefore, environmental rating systems that are based solely on cement reduction in construction may have perverse outcomes, because the engineering that supports the provision of efficient structures is ignored.

BG&E has a formal partnership with SmartCrete, considering concrete underpins the majority of the projects that the business delivers. Alternative methods to enhance the sustainability of concrete are also at play, however each scenario comes with a unique set of challenges. For instance, re-use of concrete demolition waste is constrained by transport distances, small market size and recycled materials not meeting specified requirements.

Daksh says, “It’s not about what you put into a structure but what sustainability benefits you get out of it across the lifecycle. It is essential to look at the bigger picture and cut through popular misconceptions.”

Be Part of the Solution

The material take out here, no pun intended, is there is no silver bullet to decarbonise construction – but there are many examples of success, whereby government, industry, technical experts, academia and financiers, could collectively leverage, to transform built environments.

COP26 has been referred to as “the world’s best last chance to get the runaway climate under control,” hence the time to act is now.

Sustainability is no longer something to be pursued for the sake of perception or positioning, believes Richard Palmer. As professionals in the built environment, we have a responsibility to mitigate climate change and GHG when shaping and supporting communities.

Richard says, “Sustainability is the thing we do, as engineers, architects and scientists, to fulfil our duty.”

Sources: PricewaterhouseCoopers: United Nations’ (UN) Environment Programme – Emissions Gap Report, November 2019; World Green Building Council (WGBC) – Beyond Buildings Report, October 2021; Integral Group – Launch of Contribution to WGBC’s, Beyond Buildings Report, October 2021; GatesNotes (The Blog of Bill Gates) – Buildings Are Bad For The Climate, 28 October 2019; Bloomberg Intelligence – ESG-Related Assets in United States Now Exceed the European Market, 22 July 2021; RPS – Blog Regarding What Does the Circular Economy Mean for the Built Environment, 2021; Oxford University – Essential Quotations by Susan Ratcliffe and Oxford University Press, 2016; Cement, Concrete And Aggregates Australia – A Guide to Concrete Construction, August 2020; and United Kingdom and UN – What Is A Cop, 2021.

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