Carbon and Cost Hotspots: An Embodied Carbon Management Approach During Early Stages of Design

Abstract

The need for embodied carbon management is well recognised, and possible mitigation approaches are highly sought due to the increasing need arising of carbon reduction targets. This requires the unregulated embodied carbon to be tackled instantly. This chapter presents an approach to manage embodied carbon through the identification of carbon and cost hotspots. Carbon hotspots are the elements of buildings that encompass high levels of carbon (embodied carbon). Evidence from the literature suggest that careful design of such hotspot elements will result in the highest potential carbon savings. However, the state of knowledge regarding carbon hotspots has not been extended beyond a few case studies. Hence, this chapter explored the concept of hotspots by collecting data from a sample of 41 office buildings in the UK. The carbon and cost hotspots were identified based on 80:20 Pareto rule which suggest 80% of emissions are resulting from 20% of building elements. However, findings did not fully comply with Pareto’s 80:20 ratio, instead proposed a new ratio of 80:43 for embodied carbon. Substructure, frame, external walls and services were identified as both carbon and cost hotspots of the sample office buildings. In addition, elements were categorised into three types based on the probability of an element being identified as a carbon hotspot in the building. It was interesting to note that the identified carbon hotspots were also found to be contributing up to 72% of the capital cost and the identified cost hotspots contribute up to 81% of embodied carbon. This implies that there is a possibility of reducing both embodied carbon and capital cost, which are considered as the dual currencies of construction projects, by focusing on the design of the hotspots identified.