Developing a comprehensive account of embodied emissions within the Canadian construction sector

Abstract

Construction activities are a major driver of greenhouse gas emissions worldwide. However, the majority of construction-driven emissions are indirect, meaning that these emissions occur during the manufacturing and transport of construction materials. This is in contrast with direct emissions, which are directly emitted from construction machinery. These indirect impacts are represented as embodied emissions and are difficult to quantify at scale, limiting the effectiveness of climate policymaking in the building sector. This paper presents results from a comprehensive account of embodied emissions within the Canadian construction sector, at a resolution far higher than existing global accounts, as well as novel analyses of flows and intensities of embodied emissions. It has the specific goal of serving as a baseline for future analyses of decarbonization scenarios and the more general goal of highlighting the importance of a consumption-based approach to climate policymaking in the sector. The accounts are produced via an environmentally extended input–output analysis based on Canadian supply–use tables for the year 2018, and results are presented for the 13 provinces and territories as well as 19 categories of buildings and infrastructure. Results show that demand from construction drives 13% of Canada's consumption-based emissions, residential construction is by far the largest driver of emissions, and at 0.28 kgCO_2eq per Canadian dollar of GDP, the efficiency of Canadian construction is roughly in line with the OECD average. A disproportionate share of emissions is driven by construction in provinces that are growing fast in terms of their populations, feature significant extractive industries, and feature higher emissions intensities. The construction sectors of western provinces are highly interconnected and receive a disproportionate proportion of embodied emissions from Alberta, whose high level of emissions promises to complicate decarbonization efforts. This article met the requirements for a gold-gold JIE data openness badge described at http://jie.click/badges