An attributional and consequential life cycle assessment of substituting concrete with bricks

Singapore introduced the Concrete Utilization Index to promote the substitution of concrete products with alternate building materials. This study examined the environmental impacts of replacing concrete with bricks. Using an attributional life cycle approach, it was found that replacing concrete with bricks may actually increase the net environmental impacts. In the first ever consequential life cycle assessment done for bricks in the literature, we found that replacing concrete with bricks may result in small reduction in global warming potential, provided there is no change to the amounts of bricks and concrete constituents being imported into Singapore. Considering there are changes to the import quantities, we derived a mathematical relation that enables us to know how much the import of concrete constituents must decrease in order to nullify the increased global warming potential resulted from the increase in import of bricks. In all these assessments, we found that the environmental impacts (including global warming potential) of the manufacturing stage of bricks need to be reduced. To achieve this, we reviewed a few new brick-making approaches that can produce more sustainable bricks; we also proposed a way of creating a “green demand” for these bricks and utilizing policies such as Singaporeʹs Business Angel Scheme to finance the upgrading of brick-making technologies through international partnership.