The role of Cities in decarbonizing Built Environment and Construction Sector

Buildings shape our experiences, with the construction sector contributing 13% of global GDP and 37% of CO2 emissions. By 2050, 60% of buildings will still need to be built, particularly in Asia and Africa. Sustainable practices and circular economy models are vital to meet the housing demands and reduce waste. GlobalABC’s roadmaps aim to decarbonize construction by 2050, helping countries align with climate goals and develop sustainable infrastructure. With urban populations increasing, the need for resilient, inclusive, and eco-friendly solutions is urgent to address growing challenges and achieve the Sustainable Development Goals.
Urbanization and Challenges
Today, more than half of the world’s population resides in urban areas, and this figure is projected to rise to nearly 70% by 2050. This increase will result in an additional 2.5 billion people living in cities, primarily in Africa and Asia, driven by both urban population growth and rural-to-urban migration. As urbanization accelerates, many rapidly urbanizing nations struggle to meet the demands of their expanding populations, despite the positive link between urbanization and economic development. These demands include providing adequate housing, sustainable infrastructure, reliable energy, and sustainable livelihoods for all. To address these challenges, there is a need to rethink construction practices, either by building new structures more sustainably or repurposing existing ones, to avoid further increasing the environmental burden of the construction sector.
Circularity is an essential solution to the increasing demand for natural resources:
One key solution to the construction sector’s sustainability challenges is embracing circular economy principles. The built environment consumes 12% of global freshwater and 30% of raw materials, while contributing to 20% of global effluents and 40% of landfill waste. The sector’s inefficient use of resources not only warms the climate and pollutes ecosystems but also worsens inequality. The demand for construction materials is pushing planetary boundaries to the limit, exacerbating environmental and social challenges. Construction and demolition activities generate more than one-third of global waste. The Circularity Gap Report 2023 emphasizes that adopting circular economy solutions could reduce material extraction by one-third, helping to reverse ecological overshoot. By keeping building materials in a closed-loop system, fewer natural resources would be consumed, and pollution, waste, and greenhouse gas emissions would be reduced. Moreover, the circular economy could create new jobs and economic opportunities across the construction value chain.
Climate Action Roadmaps to decarbonize the buildings and construction sector:
Since COP21, the Global Alliance for Buildings and Construction (GlobalABC) has been spearheading efforts to decarbonize the construction sector. It has developed roadmaps to guide global, national, and sub-national decarbonization efforts in Africa, Asia, and Latin America. These roadmaps aim to inspire and support countries and local authorities in reducing emissions and increasing the resilience of their built environments. By setting clear targets for the short, medium, and long terms, the roadmaps offer a comprehensive framework to align the construction sector with the goals of the Paris Agreement and the Marrakesh Partnership for Global Climate Action Pathway. The ultimate objective is to achieve zero-emission, efficient, and resilient buildings by 2050.
Global Efforts and Partnerships:
UNEP, in collaboration with GlobalABC and other partners, has been working to extend these roadmaps to the national and sub-national levels. Countries like Sri Lanka, Burkina Faso, Bangladesh, Ghana, India, and Senegal have already begun implementing these initiatives through partnerships with UNEP, UN-Habitat, and UNOPS. These efforts aim to develop national and regional strategies to promote sustainable building practices, contributing to key SDGs, particularly SDG 11 (sustainable cities), SDG 12 (responsible consumption and production), and SDG 13 (climate action). The roadmaps are helping these nations chart a path towards more sustainable, resilient, and environmentally friendly urban development.