CO₂ emission and construction cost reduction effect in cases of recycled aggregate utilized for nonstructural building materials in South Korea

The construction industry is a major consumer of natural resources and a major waste generator. The use of recycled aggregate is important for the environmental sustainability of the construction industry because it can not only reduce the need for waste landfills, but can also reduce the depletion of natural aggregates. Although there are many studies on the environmental effects of recycled aggregate, there are few studies on its practical effects as applied to real buildings. Recycled aggregates have not been widely used owing to a lack of user trust. Generally RCA has been commonly used in nonstructural materials (such as pavements or filling materials) owing to its inherent properties. Due to inferior characteristics of RCA, there is a limit to being widely used as a structural material immediately. Therefore, to expand the use of recycled aggregate, it is necessary to study the economic and environmental benefits from using recycled aggregate as a nonstructural material for buildings. In this study, the cost and potential embodied CO₂ (ECO₂) emission benefits were analyzed by using recycled aggregates as the nonstructural materials in four types of buildings, including apartments with 31 different characteristics. When applied RCA to the apartments, the cost savings are -$122,057 which is 10% reduction compared to original material. And the ECO₂ emissions cost savings amount to -$2,958 which is 5% reduction compared to original material; these represent the most effective case and reflect a −0.158% change in the total construction cost.