Building Materials – A Hidden Heavyweight for Climate Action
The “embodied carbon” in buildings comes primarily from the energy-intensive production of cement, steel, aluminum, glass and insulation materials.
The Programme for Energy Efficiency in Buildings has published a working paper presenting practical strategies to reduce embodied carbon in buildings.
In 2022, the Global Alliance for Buildings and Construction will use advocacy and research to elevate building materials and embodied carbon on the global agenda.
By Anna Zinecker, PEEB (Bonn/GIZ), and Jérémy Bourgault, PEEB (Paris/AFD)
An era of massive construction is currently underway, with a new area the size of Paris being built every week. The global building floor area is expected to double by 2060, which will have a massive impact on the climate. The production of building materials and construction activities are already responsible for 10% of global energy-related greenhouse gas emissions.
To avoid locking carbon into the system for decades, infrastructure investments have to be shifted urgently.
Building materials have a heavy carbon footprint and present a concrete challenge to the climate. The “embodied carbon” in buildings comes primarily from the energy-intensive production of cement, steel, aluminum, glass and insulation materials. The production of materials like cement also involves chemical processes, releasing additional greenhouse gases (GHGs), and leads to the depletion of natural resources like sand and the erosion of ecosystems.
Strategies to address embodied carbon – and ready solutions
We need to rethink the way we construct our buildings in order to reduce embodied carbon. The strategies to reduce embodied carbon already exist – from building smarter to decarbonising building materials. To shine a light on these solutions, the Programme for Energy Efficiency in Buildings (PEEB) recently published a working paper presenting key facts on embodied carbon, as well as practical strategies to reduce it. This video by PEEB explains the key facts.
PEEB sees three approaches: avoid embodied carbon by designing for less material use; shift to alternative building materials; and improve conventional materials by making them less carbon-intensive.
On the first strategy, avoiding embodied carbon by reducing material use, resource efficiency is the basis. We can build less, build with less materials, and build longer-lasting, more resilient buildings. = Circular approaches to construction can even turn buildings into banks of valuable materials that can be reused through “urban mining.”
The second and third approaches require a double strategy. We need swift action to reduce the emissions from the production of conventional building materials, mainly concrete and steel, but also aluminium, plastic and glass. At the same time, we need to increase the market share of alternative low-carbon materials such as bio-materials.
Low-carbon building materials and construction solutions already exist and are ready to be scaled up. Companies and start-ups across the globe have developed alternative materials which have become state-of-the-art products for today’s real estate markets. On the industrial side, large corporations like cement and steel producers are looking to decarbonise their production.
Construction in the spotlight at climate discussions
Despite its massive role in global emissions, embodied carbon from buildings is still a “blind spot” in discussions of how to reduce GHG emissions. At the UN Glasgow Climate Change Conference (UNFCCC COP 26), actors rallied to put the built environment in the spotlight. We need a “whole-life carbon” approach when it comes to dealing with emissions from the complex value chains that make up this sector..
Whilst solutions are there, dedicated policies and financing support are needed for nurturing a business environment that can tackle embodied carbon.
On 24 March 2022, the top solutions to advance policy and financing were discussed in a webinar on building materials co-organised by PEEB, GlobalABC, ABC21 and the ACT initiative. Experts from India, Morocco, France and the United States discussed the challenges and potential solutions to decarbonising building materials.
“India and Africa will add the size of Paris many times over to the world in the coming years,” highlighted architect Chitra Vishwanath from Biome Solutions in India, pointing to the massive growth in construction in developing countries. To avoid locking carbon into the system for decades, infrastructure investments have to be shifted urgently. Decisions that are taken now “will shape the production of cement and steel in 2050,” said Marlène Dresch from ACT Initiative, which supports companies in developing actionable decarbonisation strategies. She highlighted the urgency of a clear transition plan for decarbonising building materials aligned with the goals of the Paris Agreement.
Worldwide, there is an urgent need to make embodied carbon visible through better data and awareness. Building regulations still mostly target operational carbon – the energy used during the operation of a building. Performance-based building codes that include materials are only just emerging. Financing is needed to roll out technologies to reduce the carbon content from conventional building materials, and webinar participants pointed to the role of global carbon markets to accelerate this.
Anupam Badola from Dalmia Cement in India underlined the high share of construction demand from the public sector, where green procurement protocols and policies can create market demand for improved cement and steel. Asmae Khaldoun of Al Akhawayn University in Morocco highlighted the potential of bio-based and geo-based building materials as modern building materials, and their high potential to create local jobs.
What is next in 2022?
Reducing the energy use and GHG emissions caused by the way we construct is critical, and embodied carbon in buildings must be high on the agendas of policy-makers, companies and practitioners globally. In 2022, the Global Alliance for Buildings and Construction will use advocacy and research to elevate building materials and embodied carbon on the global agenda. Several members of the Alliance are working with development banks and investors to increase investments in buildings that address whole-life carbon.
This guest article is authored by Anna Zinecker, Programme for Energy Efficiency in Buildings (PEEB), Bonn/GIZ, and Jérémy Bourgault, Programme for Energy Efficiency in Buildings (PEEB), Paris/AFD.