Life cycle environmental performance of material specification: a BIM-enhanced comparative assessment

This study aims to evaluate the extent to which building material specification affects life cycle environmental performance, using a building information modelling (BIM)-enhanced life cycle assessment (LCA) methodology. A combination of the BIM-based design and analysis tool Revit Architecture, the energy simulation tool Green Building Studio (GBS) and the LCA tool ATHENA Impact Estimator were used for the assessment. The LCA was carried out on a life case study of a 2100 m2 two-floor primary-school building, as well as a variability analysis, by varying the material specification in terms of whole building materials. The life cycle performance of the buildings was primarily evaluated in terms of its global warming potential (GWP) and health impact.The findings of the study show that irrespective of the materials used, buildings that are based on renewable energy perform better than those based on fossil fuels over their life cycle. In terms of building materials, both environmental and health preferences of buildings congruently range from timber, brick/block and steel to insulated concrete formwork (ICF), in descending order. The study suggests that as buildings become more energy efficient during operational stages, serious attention needs to be given to their embodied impact.The study lays out a methodological framework that could be adopted by industry practitioners in evaluating life cycle environmental impact of different BIM-modelled material options at the building conception stage. This has the tendency to ensure that the highest proportion of life cycle environmentally beneficial material combinations are selected during specification and construction.