Achieving the Paris Agreement’s goals of holding global temperature rise well below 2 °C with efforts to limit it to 1.5 °C requires rapid reductions in greenhouse gas emissions. The built environment embodies substantial emissions, posing a challenge to meeting these goals. We quantify the carbon cost of constructing the global built-environment over the past three decades and project it to 2050. Our findings indicate that the global construction carbon footprint has doubled over the past three decades and is projected to more than double by 2050. In 2022, over half of the construction industry’s carbon emissions stemmed from cementitious materials, bricks, and metals, while glass, plastics, chemicals, and bio-based materials contributed 6%, and the remaining 37% arose from transport, services, machinery, and on-site activities. Under the business-as-usual scenario, the construction carbon footprint alone will exceed the per-annum carbon budget for the 1.5 °C and 2 °C goals in the next two decades. It will use up all remaining carbon budget for the 1.5 °C goal by 2050, as our analysis highlights. Therefore, we advocate for a material revolution, such as replacing traditional materials with biobased materials, which leverages economies of scale and paves the way for a transformative and sustainable future in construction.
Introduction.....Each year, the world’s population increases by 80 million, with projections to rise to 9.7 billion by 20501,2. Much of this growth will be concentrated in cities, placing high pressure on the need for additional housing and infrastructure3. Simultaneously, the world remains committed to ambitious goals such as the Paris Agreement, which aims to hold global temperature rise to well below 2 °C above pre-industrial levels with efforts to limit it to 1.5 °C4..
This juxtaposition creates a profound challenge. The construction of the built environment relies heavily on some of the most carbon-intensive materials, including cement, steel, and clinker5,6,7. As a result, the construction industry is widely regarded as one of the most difficult industries to decarbonize8,9. Moreover, this industry accounts for approximately 40 Gt of sand and gravel extraction and more than 20% of freshwater consumption yearly, creating additional pressure to transform the industry into an environmentally friendly one. The tension lies in how to align the carbon cost of the global built environment with global climate commitments while at the same time providing the essential infrastructure for a growing population. To untangle this tension, we must understand whether, when, and how much the global construction carbon footprint will exceed the carbon budget under the current population growth and construction development. Currently, several gaps persist in addressing this issue. First, the historical trajectory of the carbon cost of constructing the built environment remains unclear11,12,13. Even less is known about the relative contributions of specific materials and processes and how these vary across different countries (see Supplementary Note 1–3). This gap extends into the future, raising questions about the extent to which current construction trends will evolve as the built environment expands under an increasingly constrained carbon budget......read the report https://www.nature.com/articles/s43247-025-02840-x .........AND....... https://worldgbc.s3.eu-west-2.amazonaws.com/wp-content/uploads/2022/09/22123951/WorldGBC_Bringing_Embodied_Carbon_Upfront.pdf
