LFCSA Event: EMBODIED CARBON OF MATERIALS
On 25 February 2021, the Living Future Collaborative South Africa held the ‘Embodied Carbon of Materials’ event online, sponsored by Saint-Gobain. The webinar aimed to inform industry professionals about the importance of understanding Embodied Carbon – namely, the emissions related to producing materials that are used to build a building.7
Addressing Embodied Carbon
Boris Gamazaychikov, Carbon Engineer and Senior Sustainability Project Manager at Stok began the first presentation ‘Addressing Embodied Carbon’ by reminding viewers that global building stock is expected to double in area by 2060, equating to an entire New York City being built every 35 days for the next 35 years.
39% of global Greenhouse Gas Emissions come from the building sector – 11% of these emissions are embodied carbon, while 28% are operational carbon. So, Net Zero Carbon buildings, which have zero consumption during their operational phase, therefore reduce their overall environmental impact to 11%.
Gamazaychikov went on to say that 88% of the total embodied carbon of a building throughout its entire lifecycle is generated in the early Cradle-to-Gate stages – that is, the processes of material extraction, transport to factory, and manufacture. In this respect, the highest impact materials are concrete, steel and paint.
Holistic Embodied Carbon Reduction strategies are therefore essential to minimising the negative impact of construction. These include using mass timber sourced from sustainably managed forests (FSC); specifying more durable products; reusing existing structures and reducing the amount of structure required. All sector professionals have a role to play in making this happen including architects, structural engineers, contractors, manufacturers, and policy makers.
The Uptake of Secondary Raw Materials from Manufacturing into the Construction Sector
Oliver Bonstein, Western Cape Industrial Symbiosis Programme (WISP) Facilitator at GreenCape, then discussed ‘The Uptake of Secondary Raw Materials from Manufacturing into the Construction Sector’. He advised that the building industry is one of the largest sources and sinks for waste (secondary raw materials). WISP has worked with manufacturers and construction companies to stimulate demand for previously unwanted materials – which include builders’ rubble that led to the uptake of 18,000 tonnes of unassigned rubble for roads bases, foundations and crushed aggregate.
Ash from coal boilers has become a feasible additive to various cement or clay mixtures and, to date, WISP has facilitated the uptake of more than 10,000 tpa of ash waste into brick making applications. Other materials that have been recycled back into the industry through synergies enabled by WISP include gypsum, textiles, wood, glass waste and polystyrene.
GreenCape also sought to assist manufacturers and builders to reduce their water consumption and to find alternatives to potable water during the serious regional drought experienced in the Cape (2017-2018), when the uptake of treated effluent and untreated ground water was identified as a viable solution.
Finally, Bonstein introduced DigiYard, an app idea by Arup that aims to reduces material losses and preserve the value of materials by enabling a reuse market to repurpose usable construction waste.
Tools to Decarbonize Global Construction
The closing presentation was given by Aditi Chitnis, LCA & EPD Business Development at One Click LCA in Finland, who presented ‘Tools to Decarbonize Global Construction’. This looked at how to calculate the embodied energy of a building and what tools are available. Chitnis opened with the statement that most emissions are determined during the early stage of planning, and that decisions in projects determine a building’s emissions for many years to come. The Embodied Carbon Pyramid gives an idea of the order in which project leaders should start making these decisions.
One Click LCA is an easy automated lifecycle assessment software that helps professional consultants to calculate and reduce the environmental impacts of buildings and infrastructure projects, products and portfolios. The platform enables specifiers to find materials easily and clarify material quantities, and to access material carbon benchmarks with data from all manufacturers globally. Chitnis concluded by presenting a smallscale case study of the Bionova office renovation in a 19,000sqm industrial building in Helsinki.
This free ‘Embodied Carbon of Materials’ webinar is CPD-validated by SACAP and ECSA and is available online: https://www.greened.co.za/courses/embodied-carbon-of-materials/