Greenhouse gas emissions of global construction material production

Abstract

Global production of building materials is a primary contributor to greenhouse gas (GHG) emissions, but the production of these materials is necessary for modern infrastructure and society. Understanding the GHG emissions from building materials production in the context of their function is critical to decarbonizing this important sector. In this work, we present estimates of global production, approximate ranges of GHG emissions, and ranges of material properties of 12 critical building material classes to provide a unified dataset across material types. This dataset drew from industry analyses of production and emissions, ranges of emission factors within a material type, and broad reporting of thermal and mechanical properties to compare both within and between material types. Globally, in 2019, we estimate 42.8 Gt of these 12 materials were produced, with 38.6 Gt used in the building and construction industry. As a result of this production, 9.3 Gt of CO2 was emitted, or 25% of global fossil GHG emissions, with 5.8 Gt CO2 (16% of global GHG emissions) due to materials used in construction applications. Both construction material production and emissions are primarily driven by structural materials, such as concrete and steel. Material selection can play a key role in reducing emissions in the context of the function, with variation in emissions of structural materials per unit strength between 0.001-0.1 kg CO2/kg/MPa and in insulation materials per R-value/thickness of 0.018-0.14 kg CO2/kg/(K⋅m2W−1))). The developed dataset can play a key role in supporting decision-making in materials by providing a unified source for examining emissions, material properties, and quantity of material produced.