Construction-related activity accounts for roughly 23 percent of global greenhouse gas emissions, according to figures cited in New York City’s latest climate initiative, placing material production and building processes among the largest but least regulated contributors to urban carbon footprints.
In response, New York is shifting its decarbonization strategy beyond building operations to focus on emissions embedded in construction itself, a category known as embodied carbon.
The initiative, led by researchers at New York University in collaboration with Rutgers University, is examining emissions generated across the full construction lifecycle, including cement production, steel fabrication, material transportation, and on site installation. The work is funded by the New York City Mayor’s Office of Climate & Environmental Justice and is intended to establish a baseline for future regulatory benchmarks.
That baseline matters because embodied carbon is still inconsistently measured across construction markets, despite its growing share of total emissions. Cement alone is estimated to contribute approximately 8 percent of global carbon emissions, a figure that has remained structurally high due to the energy intensive nature of clinker production and limited large scale substitution of low carbon alternatives in structural applications.
The research effort comes as New York advances a policy trajectory aimed at cutting construction sector emissions by 50 percent by 2033. The city has already moved to integrate embodied carbon considerations into public procurement frameworks through earlier executive directives, signaling a gradual tightening of material selection criteria for publicly funded projects.
Mayor Zohran Mamdani has positioned embodied carbon reduction as both an environmental and cost efficiency issue, arguing that material optimization could reduce emissions while lowering construction expenses. The economic assumption underpinning this approach is that reduced material intensity, combined with lower carbon inputs, may decrease long term lifecycle costs, although this outcome depends heavily on substitution availability and market pricing of alternative materials.
The research team is now evaluating how emissions are distributed across construction stages, with particular focus on cement, steel, and glass production chains. These materials dominate embodied carbon profiles in urban infrastructure because of their high energy input requirements and reliance on fossil fuel based industrial processes. Steel production alone remains heavily dependent on coal based blast furnace systems globally, although electric arc furnace capacity is expanding in some regions.
A key objective of the study is to quantify emissions at a granular level so that future policy interventions can target specific stages of the construction supply chain. According to project lead Semiha Ergan, an environmental engineering professor at New York University, establishing a credible baseline is essential for tracking progress over time. Without standardized measurement frameworks, reductions risk being difficult to verify or compare across projects.
The city estimates that approximately 2 million metric tons of carbon dioxide were emitted in 2020 from construction related machinery and industrial operations within New York City alone. While that figure captures operational construction emissions rather than full embodied carbon, it illustrates the scale of activity associated with ongoing urban development in one of the world’s densest construction markets.
Industry response has been mixed but increasingly pragmatic. Contractors are beginning to test lower carbon approaches such as recycled aggregates and warm mix asphalt, which reduces production temperatures compared with traditional hot mix processes and can lower associated emissions. However, adoption remains uneven due to supply chain variability and performance uncertainty in some applications.
Melinda Tomaino, senior director of environment and sustainability at the Associated General Contractors of America, noted that adoption barriers often stem from familiarity rather than technical feasibility. New materials tend to face slower uptake when contractors lack operational experience with them, even when performance is comparable to conventional alternatives. That friction highlights a broader structural issue in construction decarbonization, where innovation cycles move more slowly than policy timelines.
This tension between policy ambition and industry readiness is becoming increasingly relevant as cities attempt to regulate embodied carbon more directly. Unlike operational emissions, which can be reduced through electrification and energy efficiency upgrades, embodied carbon requires upstream changes in global industrial supply chains. That makes local policy interventions dependent on broader market availability of low carbon materials, which remains uneven across regions.
New York’s approach reflects a growing trend among large cities to influence global construction emissions through procurement rules and design standards rather than direct industrial regulation. By setting carbon thresholds and encouraging material optimization strategies such as reduced material use in structural design, policymakers are attempting to shift demand signals upstream into manufacturing sectors.
