Chapter 6
6.1
Measurement and Data Are Improving, But Transparency and Verification Are Needed 
6.2
Existing Tools for Assessing Carbon Impact
6.3
Recommendations for Future Carbon Assessment Tools
6.4
Tools for Greenhouse Gas Assessment Are Needed for District-Scale Planning
6.5
Global Standards and Labels for Emission Transparency Can Galvanize the Market
6.6
Challenges and Next Steps

Table 6.2

Emerging mechanisms to support whole life-cycle decarbonisation of building materials

Performance-based building codes

The emergence of low-cost tracking has enabled greater access to demand-side metrics on energy and water use in buildings. Transitioning to performance-based building codes that draw on these metrics could transform well-established codes. It would also lend a critical opportunity for emerging economies lacking existing building energy codes to leverage their ongoing building boom to leapfrog over outdated prescriptive building codes, which were largely based on “best practice” examples, with “one-size-fits-all” guidelines that are ill suited due to the variability of local micro-climates and building traditions. Performance-based building codes have a greater chance to connect to a range of stakeholders, from global architecture, engineering and construction companies, to owner-builders in informal settings.

Examples: EnergyPlus, Zero Tool,  Building Energy Modelling, Autodesk Energy Analysis, Sefaira Building Performance Software,  PV Calculator, DSIRE Efficiency/Energy Incentives Database,  WUFI.

Carbon footprint assessments

Emerging carbon footprint assessments convey more transparently the potential whole life-cycle impacts of embodied and operational carbon, both for traditional construction materials and for prefabricated systems and assemblies. Through critical comparisons, stakeholders can consider and track the beneficial impacts across the life cycle of computer-enhanced design, procurement and production methods. These benefits can include increasing the efficiency of materials and structures, reductions in on-site emissions from construction, and the improved ability within factories to design for disassembly and circular reuse/recycling. However, anticipating the impact of materials on operational performance is complex and needs to account for factors such as local bioclimate, building typologies, systems integration, and human behaviour and occupation patterns. All of these can cause great variability in the operating performance of a building material and its system.

Examples: EC3 Carbon Calculator, Tally, WoodWorks Carbon Calculator, Athena Impact Estimator for Buildings, Open LCA, GLAD

Embodied carbon labelling

Wide discrepancies currently exist in the methods and quality of the labelling of embodied carbon in building materials. Support is growing for the establishment of an international standards committee to oversee fairness in this labelling. However, more development is needed of methods that address the “carbon loophole,” so that the consumers and specifiers of materials in countries with strict pollution controls can share accountability with producers from regions with lax controls. Unfortunately, the inability of many producers (particularly small ones) to pay for the certification of their products can lead to them being further disadvantaged by carbon border taxes – thus leading to the further loosening of local regulations to ensure that exports remain competitively priced.

Examples: EC3 Carbon Calculator, Cradle to Cradle certified, Declare Living Future Institute.

Low-carbon public procurement practices

Municipal and national governments are setting policies and aggressive targets that limit their choices to low-carbon alternatives when selecting contractors. This is resulting in the establishment of leading industry precedents for integrated decarbonisation across multiple scales of infrastructure and buildings.

Example: See Box 6.2 on Helsinki, Finland

Industry pledges

Global leaders in the architecture, engineering and construction industry are developing pledges, internal benchmarks and novel methods to track the carbon impacts of their activities. Despite rampant accusations of greenwashing, with many risks of data manipulation (especially when self-reported), rating agencies and efforts such as the Science Based Targets initiative work with businesses to agree to a science-based target that limits a business’ global share of greenhouse gas emissions, with independent verification. However, firm commitments need to be secured. The climate pledges made at the 2021 United Nations Climate Conference in Glasgow were followed by lawsuits for greenwashing in advertising; thus, many firms are choosing to avoid scrutiny.

Examples: Green Building Principles: The Action Plan for Net-Zero Carbon Buildings, Sustainable Construction Leaders Peer Network, Contractor’s Commitment to Sustainable Building Practices

Models for coordination

Models for coordination across the forestry, agriculture and construction industries are emerging for enhanced cooperation on land use and the supply of bio-based building materials. The aim is to develop supply chains and products derived from the upcycling of forest detritus and agricultural waste by-products into building materials, which would in turn greatly reduce carbon emissions from forest fires and crop burning.

Example: Build Carbon Neutral Calculator

Carbon offsets

As governments, industry players and others strive to meet net zero emission deadlines, demand is growing for carbon offsets and renewable energy credits. This is setting the stage for an escalating carbon offset economy. However, the actual decarbonisation of building material production processes may be hampered by the ability of industries to market so-called net zero products through the use of carbon offsets of varying quality. Greater regulation is needed in certifying decarbonisation of the actual processes of material production.

Example: See Box 6.3 on Lendlease Americas.

Global Standards and Labels for Emission Transparency Can Galvanise the Market

If all G7 economies implemented policies that favour low-carbon materials and products, global emissions could be reduced 5.5%.

OR Developed economies that are net importers of raw materials need to commit to low-carbon materials and products while ensuring fair trade and labour practices.

It is essential that all of the different methods for identifying and declaring materials-related greenhouse gas emissions be brought into globally regulated compliance through transparent labelling. This would help create a level playing field across the supply chain and life cycle. Material producers – particularly in emerging economies where resources for certification are limited – must be supported to enable fair, third-party verification of processes and equipment. For purchasers of materials, such independent verification is needed by supplier, assembly, installation, geography and asset.

The most impactful way to facilitate multi-stakeholder cooperation across global material supply chains is to “close the carbon loophole.” This means that developed economies that are now net importers of raw materials – and that have contributed the vast majority of past greenhouse gas emissions – should not be permitted to purchase those materials at “discounted” prices from emerging economies, which are obligated to maintain low prices through lax environmental and labour regulations. Global cooperation is needed to create a new trade paradigm. If all G7 economies implemented policies that favoured low-carbon materials and products, while ensuring fair trade and labour, global emissions could be reduced by 5.5 per cent (1.8 gigatons of CO2) (IEA 2021).

This would also create a far more equitable system for tracking emissions across the material life cycle. Closing the carbon loophole would provide pathways for producers in the developing world to gain access to new markets, by shifting emissions off the balance sheets of developing economies and placing more accountability on consumers in high-income countries that boast strict environmental regulations at home. Furthermore, a level playing field is essential for the creation of transparent and verifiable international labelling and certification protocols. Public education and policy are critical to ensure that consumers have a better understanding of the social and environmental costs of cheap materials, from forced labour to the degradation of ecosystems, species loss, forest fires, water and air poisoning, etc.

The demand for low-carbon materials can be bolstered by market-based mechanisms, financing, certifications and regulations to lower risks and create a fair, competitive playing field. Border carbon adjustments, such as the European Union-led Carbon Border Adjustment Mechanism, or trade agreements like the U.S. proposal for a Global Arrangement on Steel and Aluminium, both announced in December 2022, are examples of policy instruments that intend to minimise the risk of unfair competition and “carbon leakage” in cross-border carbon accounting.

However, if these mechanisms are to truly support global decarbonisation, then their design must account for the realities of production and demand in emerging economies. Global agreements on carbon-adjusted building material markets and financing should build capacities for transparently identifying and verifying carbon competitiveness, so that materials can be fairly certified (Brenton 2021).

Developments in international trade mechanisms may be able to change the game in combating global climate change. However, for emerging economies that have historically contributed very little to climate change, but where the majority of material production and consumption will take place in the coming decades, it is critical to facilitate the development of a consistent and comprehensive accounting system to accurately measure emissions all along the life cycle and value chain, so that these countries have a fair chance to demonstrate their carbon competitiveness (Columbia Center on Sustainable Investment [CCSI], International Institute for Environment and Development [IIED] and International Institute for Sustainable Development [IISD] 2021). To truly create a level playing field towards global decarbonisation, many emerging economies have taken the position that they should receive a large portion of the proceeds from border carbon adjustments, to support them in adopting low-carbon methods and certifications.

Table 6.2 provides an overview of some of the mechanisms, including carbon labelling, that are emerging to support whole life-cycle decarbonisation of building materials in both developing and developed countries. Box 6.3 provides an example of how one company, Lendlease Americas, used life-cycle analysis to inform multiple concurrent decarbonisation pathways on the path to net zero.

Box 6.3

Net zero construction at Lendlease Americas

The global construction company Lendlease Americas was able to reach net zero emissions for its roughly $2 billion construction operations during 2021 and 2022. The company used life-cycle analysis to inform multiple concurrent decarbonisation pathways. To maintain alignment with a pathway to keep global temperature rise below 1.5 degrees Celsius, Lendlease has committed to achieving carbon neutrality in its scope 1 and scope 2 emissions by 2025, and absolute zero carbon emissions across scopes 1, 2 and 3 by 2040. The company achieved its 2025 goals early for its U.S. construction business, largely by reducing its significant operational emissions.

During financial years 2020 and 2021, Lendlease’s U.S. operations released a total of 15,799 metric tons of CO2-equivalent emissions. Of this, scope 1 emissions totalled 9,411 tons, derived from the use of fuels for temporary construction electrical power generation and fuels used in operating major plant and equipment such as excavators and tower cranes. Lendlease used natural gas and other fossil fuels to provide heating during concrete placement in colder winter months. In addition, the company emitted indirect scope 2 emissions totalling 6,390 tons through the use of electricity for site lighting and other temporary uses.

Lendlease is implementing the following strategies to reduce both scope 1 and scope 2 emissions:

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utilising electric plant and equipment through expediting permanent power utility connection

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use of biofuels and renewable diesel

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leveraging battery storage solutions to reduce generator sizing

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eliminating fossil fuel heating of concrete placement operations during winter months

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leveraging on-site renewables such as solar for small-scale applications

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purchasing carbon offsets and renewable energy credits.

Lendlease chose several U.S. renewable energy projects to procure carbon offsets for its scope 1 emissions, and also purchased high-quality renewable energy credits for its scope 2 electricity use. Through these measures, Lendlease Americas Construction has been operating “net zero” since July 2020. Lendlease believes in the importance of sharing best practices for reducing carbon emissions associated with construction and collaborating with peers to rapidly decarbonise this industry.

Source: Lendlease 2022.