Comparison of the environmental performance of ceramic brick and concrete blocks in the vertical seals' subsystem in residential buildings using life cycle assessment

Abstract

This work presents an evaluation and comparison of the environmental impacts generated in the vertical sealing subsystem of a single-family residential unit, using the methodology of Life Cycle Assessment (LCA) to evaluate the environmental impacts of ceramic blocks and concrete blocks applied in the same unit. The research is justified by the possibility of using LCA method to increase the sustainability of the construction process. The novelty herein is to identify the critical points (i.e. the respiratory effects, the intensive use of fossil fuels, and the consequent climate changes) in the LCA of the building materials of two types of masonry commonly used in Brazil, namely ceramic blocks and concrete blocks. The method adopted is following the recommendations of ISO 14040 and ISO 14044, including the four main phases. It was also integrated the EcoInvent as an endpoint method and Eco-indicator 99. Ecoinvent is of foreign origin, it does not accurately portray the Brazilian reality, however, it was used because there are still no data at the national level. The Analysis of the environmental impact of particular systems may help select building materials, about the environmental performance at an early designing phase of buildings. Categories were established based on the endpoint categories that are ecosystem quality (EQ), human health (HH), and natural resources (R). This work insight that the ceramic blocks appear to have the highest impacts concerning the R, with 46%, while for the same impact the production of the concrete block represents 69%. There is still a higher environmental impact in the case of masonry in concrete blocks, mainly due to the brick burning stage in the cement manufacturing process. The masonry in ceramic bricks has its highest impact due to the step of burning the bricks. It is noted that both construction methods have the same critical points, however, the analysis of the environmental impact of particular systems may help select building materials, concerning the environmental performance in the early project phase. As a scientific contribution this study shows that LCA methodology can be a very useful and appropriate tool in sustainability studies in the construction industry. It is recognized that despite the inherent limitations of conducting an LCA based on a case study, the results will serve as a benchmark for Brazil brick production.