Urban development is booming, and with that growth comes a big responsibility: the buildings we raise today shape our cities’ emissions for decades. Construction and building operations together account for a large share of urban greenhouse gas emissions, meaning every new project carries a carbon cost. Tackling those emissions in the construction phase gives cities a real chance at reaching net-zero targets. In this article, we’ll walk through how the building sector contributes to urban emissions, how decarbonizing construction methods supports net-zero cities, and what cities and industry players need to do next.
Quick look
- Construction and building operations account for nearly 40% of global CO₂ emissions, making the sector central to net-zero goals.
- Embodied carbon from materials like cement and steel is now rivaling operational emissions from heating, cooling, and lighting.
- Decarbonizing construction means shifting to low-carbon materials, electric equipment, and energy-efficient design.
- Cleaner construction supports healthier cities, new green jobs, and alignment with climate investment policies.
- Achieving real progress will require stronger regulation, industry collaboration, and workforce education on sustainable methods.
Construction’s role in urban emissions
The built environment is responsible for a significant share of global emissions. According to data from the International Energy Agency (IEA), the operations and construction of buildings accounted for more than one-third of global energy-related carbon emissions. Additionally, a United Nations Environment Programme (UNEP) report states that the buildings and construction sector accounts for about 37% of global greenhouse gas emissions.
In urban areas, this means that every new high-rise, every infrastructure expansion, every housing complex adds to that total. Major emissions originate from the manufacturing of materials such as cement, steel, and aluminum, from the construction process itself, and from the ongoing energy use of the building—including heating, cooling, lighting, and ventilation. The “use phase” of a building generates high emissions in cities because of the density and intensity of activity. On top of that, the “make/build” phase adds embodied carbon that cannot be ignored.
Embodied vs operational carbon
Embodied carbon refers to the emissions generated upstream: extraction of raw materials, manufacturing, transport, construction, and eventual demolition or reuse of materials. Operational carbon refers to the emissions from energy use and services to operate the building over its lifetime.
In many older cities, operational carbon dominates because buildings were built with less efficient systems. However, as buildings become more efficient and grids shift toward renewables, embodied carbon becomes an increasingly larger share of emissions in new builds. That means if we only focus on reducing operational emissions, we still leave a large “hidden” carbon load in new construction.
Urban growth and infrastructure demand
Cities around the world continue to expand at a rapid pace. According to data from the Global Alliance for Buildings and Construction (GABC), the global floor area is expected to grow significantly over the next few decades.
This growth means more buildings, more materials, more construction sites, and more carbon. For cities planning infrastructure, that means decisions today matter for decades. If each new project uses high-carbon materials or inefficient methods, the cumulative carbon load can overwhelm emissions budgets. Tackling emissions in construction is no longer a “nice to have” but a necessity if cities are aiming for net-zero.
How decarbonizing construction enables net-zero cities
Reducing emissions in construction and building operations offers cities a path to reach their climate goals while growing. Cleaner construction methods mean less carbon locked in immediately, and better building design means less carbon emitted over the lifetime of the structure.
Reducing embodied carbon in materials
One of the first steps is to switch to low-carbon materials, such as low-carbon concrete mixes, recycled steel, and engineered timber. By choosing materials with lower upfront emissions, builders can reduce the carbon “spent” before occupancy. When cities adopt procurement standards that require low-embodied-carbon materials, the whole supply chain shifts. This matters because once embodied carbon is emitted, it cannot be undone—and that contributes to a city’s carbon budget for decades.
Electrifying equipment and transport
Construction sites themselves contribute to emissions through diesel-powered machines, trucks delivering materials, and the logistics of construction. Switching to electric power, utilizing renewable energy for site operations, and optimizing transport logistics reduce those emissions. In practice, moving away from diesel excavators and concrete mixers, and using battery-powered or hybrid alternatives, means construction becomes part of the decarbonization plan. When materials arrive via low-emission logistics, the entire build’s carbon footprint is reduced.
Designing for energy efficiency and reuse
Once a building is erected, its energy use often accounts for a large share of its lifetime emissions. Designing with passive features, efficient systems, and the potential for reuse or retrofit locks in lower operational carbon. Pulling in circular design—reusing parts of existing buildings, planning for adaptability, and designing for long service life—reduces the need for frequent rebuilds or replacements that generate fresh embodied carbon. For a city aiming for net-zero, buildings that use less energy, last longer, and can adapt to future needs reduce the load on urban energy systems, allowing for more aggressive climate targets.
The ripple effects for cities
Cleaner air and healthier communities
When construction emissions decrease and building operations become more efficient, cities experience improved air quality. Reducing on-site and building-system reliance on fossil fuels means fewer pollutants and better health outcomes for workers and residents.
Economic resilience and green jobs
Decarbonizing construction drives demand for new skills, including low-carbon materials, electric site equipment, retrofit specialists, and circular economy experts. That creates green jobs in cities and supports economic resilience as urban centres modernize.
Alignment with climate policy and investment
Cities with strong decarbonization strategies in construction attract investment from funds prioritising green infrastructure. When a municipality establishes rules regarding embodied carbon and efficient building design, developers tend to align. That means better project financing, lower risk, and a path for cities to meet their climate targets on time.
What needs to happen next
Stronger regulation and lifecycle carbon tracking
Regulations must require lifecycle carbon tracking—not just energy use once the building is occupied, but the carbon emitted from materials, construction, transport, and end-of-life. Cities need transparent standards for embodied carbon in buildings and procurement rules that make low-carbon materials the default.
Collaboration across supply chains
Manufacturers, builders, designers, and city planners must work together. Procurement, design, construction, operations—those phases cannot work in silos. If a developer orders low-carbon concrete but the subcontractor uses traditional logistics or site processes, the benefit is lost. Full supply-chain alignment is required.
Innovation and education in the workforce
The construction workforce must be trained in new methods: electric equipment, circular design, and low-carbon materials. Vocational training, site-based upskilling, and awareness campaigns need to match the technology. When the team on site understands why material choice matters and how the equipment works, projects run more smoothly and deliver carbon savings.
Final thoughts
Decarbonizing construction has more impact than many realize. Because buildings and infrastructure carry carbon from day one, the way we build matters just as much as how we power what we build. Cities that commit to low-carbon construction will set themselves ahead—and for architects, builders, and engineers, embracing smarter materials, cleaner equipment, and better design is how you deliver those cities.
For more on building smarter and cleaner, check out these articles on Canada’s first zero-carbon aquatic centre, biodiesel in construction, and biochar use.
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