The world population is constantly growing, and every year more and more infrastructure must be built to accommodate this growth. As material needs increase along with the rising global population, diverting waste through recirculation is one of the most effective methods of scaling infrastructure without irreparably affecting our natural environment.
The Ellen Macarthur Foundation states that the circular economy “tackles climate change and other global challenges, like biodiversity loss, waste, and pollution, by decoupling economic activity from the consumption of finite resources.” According to RBC, Canada will need 5.8 million new houses by 2030—adding up to 18 million tonnes of GHG emissions to the nation’s annual output. With more than $40 billion a year required in capital investment to meet this demand, incorporating circularity into construction standards and practices will be essential for reducing embodied carbon and material waste in industrial sectors.
The seventh annual World Circular Economic Forum was held in Finland in May and June 2023. According to its Summary Report, discussions at the Forum revolved around moving the circular economy out of the future and into the present, shifting the focus from “why” to the “how and now” and highlighting the importance of communication, collaboration, and trust.
While nature often takes priority in circular economy discussions, the built environment and its decarbonizations are essential facets of sustainable developments. At the WCEF, the Circular Buildings Coalition (CBC) launched its report titled “Towards a Circular Economy in the Built Environment,” sharing stakeholders’ thoughts on incorporating circularity into the built environment’s standards and practices.
The report estimates that “in a ‘business-as-usual’ scenario, the EU27+UK’s construction sector will exceed its allocated carbon budget for limiting global warming to 1.5°C in 2026. Furthermore, the budget for 1.7°C and 2.0°C will run out in 2029 and 2031 respectively, if no action is undertaken.” In order to reduce these emissions, the built environment and its approach must move from the current linear model—dubbed “take-make-waste”—to a circular one.
The CBC report makes particular note of the construction industry and its place as a key consumer of materials: “globally, the construction sector accounts for approximately one third of total material consumption, contributing to a threefold increase in global material extraction since 1970.” Circular construction solutions proposed by the report include using materials with low embodied carbon impacts, like secondary materials, especially in the “Renovation Wave” in Europe—the EU expects a 3% annual renovation rate in coming years.
According to the Circular Buildings Coalition report, “if the EU27+UK’s construction industry were to become ‘zero-waste’ while current demand remained unchanged, secondary materials could replace up to 12% of virgin materials,” leading to over €1.8 trillion annually in economic benefits.
The report notes that, when it comes to embodied carbon and emissive industries in the EU, the cement and steel industries are “significant drivers of this impact, contributing a combined 66% of all emissions.” Concrete makes up nearly 75% of total material consumption by weight in the EU, and is likewise responsible for nearly 40% of total emitted CO2e. Through increasing the uptake of secondary materials in steel slag-based cement-free, carbon-sequestering concrete, CarbiCrete can address the emissions and waste of both these industries.
The Ellen Macarthur Foundation’s Built Environment report remarks that “A circular economy could reduce global CO2 emissions from building materials by 38% in 2050, by reducing demand for steel, aluminium, cement, and plastic. It could also make the sector more resilient to supply chain disruptions and price volatility of raw materials.” Through utilizing steel slag, a byproduct of industrial steelmaking, in the CarbiCrete process, concrete products can be produced with no harmful cement and a negative carbon footprint. The steel slag reacts with CO2 in a proprietary curing chamber, creating durable and environmentally-friendly masonry. With both steel slag and CO2 supply streams working to divert waste, CarbiCrete’s contribution to the circular economy is significant for both construction and sustainability.