The value of Buy Clean policies is indisputable. They use government purchasing power for public works to drive down greenhouse gas emissions, encourage innovation, and foster green industry. 

Buy Clean policies mandate the use of construction materials and products with lower embodied carbon impact across supply chains and use incentives to encourage participation and innovation.

Their objective is to accelerate the transition to a net-zero economy by spurring green infrastructure, buildings, manufacturing, and domestic job growth. Such policies’ potential to reduce embodied carbon can be significant — in the US approximately 32% of construction-related embodied energy and carbon comes from public projects.

Creating viable, actionable Buy Clean policies is complex and challenging, however. Historically, well-intentioned policies have been stymied by unforeseen barriers and misalignments between regulations and the realities of implementation. To move to a more effective phase of Buy Clean policy making, the construction industry must forge a process that considers the whole-asset and its life cycle, prioritizes input from an expansive set of stakeholders, integrates multiple levels of government and local needs, and rethinks how we can best achieve lower carbon outcomes.

Green public procurement on the rise

Ambitious national programs have the advantage of using expansive, overarching policy to leverage the scale of government procurement for a shift towards lower-carbon options. With government projects typically comprising 12-30% of a country’s gross domestic product, national Buy Clean policies can meaningfully advance green industry for buildings and infrastructure.

While the US federal government established a Buy Clean policy in 2020, the landmark Inflation Reduction Act of 2022 is enabling consequential progress towards growing a green economy. Canada and the EU have taken note. In 2021, Canada committed to a Buy Clean strategy for public sector building and infrastructure projects. In 2023, the EU announced a plan providing funding for scaling the manufacturing of clean technologies. These policies have the benefit of learning from Buy Clean programs that came before them, both for what has worked and where such policies faced impediments.

Listening far and wide

To best anticipate and address these challenges and establish more productive regulations, policymakers should begin by integrating input from regional stakeholders and across supply chains. This helps surface and plan for the obstacles they may encounter on their journeys toward decarbonization.

Recommendations for Canada’s forthcoming Buy Clean policy were informed by deep engagement across a variety of relevant stakeholders. Initiated by the Future of Infrastructure Group and the Buy Clean Industry Alliance and co-chaired by Arup, the recommendations were developed using an interview and workshop format to formulate a common set of suggestions and principles. The resulting report, “Building Success: Implementing Effective Buy Clean Policies,” draws on participation from material producers, industry trade groups, specifiers, contractors, owners, academics, and government.

“Building Success” includes several pioneering approaches for bridging the gap between policy and funding and the reality of implementation. While these strategies are designed for Canadian infrastructure procurement and reflect the nuances of the country’s industries and regulatory frameworks, they provide constructive approaches that have universal relevance for Buy Clean policies globally.

A whole-asset life cycle focus

Typically Buy Clean approaches focus on materials for individual product categories, prescribing emissions limits to help create markets for lower-carbon concrete, steel, or other hard to abate materials. This approach reduces the carbon impact of the individual product used; however, it only considers the initial product stage emissions and does not incentivize optimized resource use across the whole asset and its life cycle.

The Canadian report departs significantly from this strategy, encouraging emissions reductions in design and construction, as well as in material choices. It puts forth a model where a request for proposal specifies an emissions goal for the performance of a whole project for the full-service life of the asset. By encompassing a more comprehensive set of conditions, it invites a broader array of solutions. This can yield an equal or greater impact relative to material level requirements.

The Canadian report departs significantly from this strategy, encouraging emissions reductions in design and construction, as well as in material choices.

To lower carbon, designers are motivated to rethink standard processes and material use, such as to design for longer service life or for disassembly. For a 100-year project where durability and resilience are critical, for example, using a concrete structural system designed for the full-service life may result in lower life cycle embodied carbon compared to other alternatives that would require replacement.

Carbon performance requirements can also lead project teams to be more mindful of material efficiency and material reuse. This elevates recycled and reduced material use and encourages retrofitting structures as viable solutions. In turn, material producers are encouraged to develop competitive products to meet demand.

When carbon requirements are included in a request for proposal, decarbonization discussions occur earlier in the process, expanding conditions for collaboration within the industry. Using carbon as a performance metric for procurement decisions motivates project teams and bidders to identify opportunities and innovate for emissions reductions in design and construction and material choices.

This was the case of one of Arup’s rail platform reconstruction projects for VIA Rail CanadaAlthough VIA Rail did not specify detailed decarbonization targets, measures, or metrics, it did express sustainability ambitions within their request for an engineering consultant proposal. Therefore, to support this ambition, we initiated greenhouse gas emissions mitigation targets and solutions, beginning with identifying the key emitting component — the concrete barrier curbs. Then we established an industry standard benchmark using typical details and material standards.

To yield achievable and practical outcomes aligned with the client’s vision, we optimized the structural design of the curbs, minimized reinforcing steel, and then prescribed global warming potential (GWP) performance requirements to be met by the concrete supplier. Arup included the GWP in the construction tender documents, which enabled bidders to propose eligible concrete mixes and decarbonization measures. This early engagement enabled a competitive bidding environment, with low risk to the client and bidders. Our engineering team then worked with the selected contractor to validate the concrete mix details and ensure accurate reporting and disclosure.

Ultimately, through design optimization and GWP performance specification, we achieved a 50% embodied carbon emissions reduction against the benchmark at no cost difference and no schedule impact.

When carbon requirements are included in a request for proposal, decarbonisation discussions occur earlier in the process, expanding conditions for collaboration within the industry.

The data conundrum

For any lower carbon emissions requirements to be meaningful, we need reliable data. This enables the development of accurate emissions measurements, valid limits, and industry average baselines. Yet the construction industry’s glaring lack of complete, up-to-date carbon data, along with the need for urgent action create a paradox.

“Building Success” advocates integrating life cycle assessments into the whole-asset approach where possible. This demands a greater focus on considering and tracking greenhouse gas emissions arising from the manufacturing, transportation, installation, maintenance, and disposal of building materials used in construction. The intended result is to advance decarbonization for the industry through increased data collection, reporting, transparency, collaboration across supply chains, and collective knowledge.

The recommendations also advocate for predictable, performance-based requirements that ramp up over time. This includes beginning with an initial flexibility to accommodate the lack of data. As the industry makes advances in data collection and accuracy, product and material development, and design solutions, regulations can become increasingly stringent to encompass embodied carbon more fully across project life cycles.

Innovating for industry impact

Especially in these early days of transitioning to net zero, innovation is crucial for uncovering new ways to lower carbon emissions. Innovations, even on small projects, can lay the groundwork for scaling solutions for much wider implementation. Experimentation can generate and test novel design solutions that may result in even more aggressive carbon reductions than a standard might require.

This is why it’s so important for Buy Clean policies to build in opportunities for pilot projects and incentivize and leverage the strengths of all project players. They can also reward frontrunners with bid discounts for those meeting the highest tier of lowest emission options or use a point system based on predicted emissions performance of a project. Gain-share incentive mechanisms split cost savings between government and bidders derived from interventions that reduce embodied emissions, which can encourage engineers and contractors to find cost-effective emissions solutions.

Buy Clean policies have enormous promise to be effective drivers for decarbonizing public sector buildings and infrastructure — and potentially advance the industry at large towards net-zero goals. The construction industry needs to gather wide-ranging input and feedback when developing policy and codes. To achieve more aggressive lower carbon solutions, we need to approach projects holistically, bringing flexibility, collaboration, and creativity to the process. And by moving towards life cycle requirements in Buy Clean policies, we shift the focus to long-term thinking, which may help foster greater awareness of the danger of and bring solutions to a rapidly warming planet.