Building information modeling (BIM) and life cycle assessment (LCA) are two methods that can be helpful when designing buildings with lower environmental impacts. One of the most significant examples of environmental impact assessments in construction is green building certification. Certified buildings have improved performance and greater asset value. In this study, four certification systems were investigated for their potential interconnections with BIM and LCA. The main tasks were (1) to review a BIM-based workflow, (2) assess its usage as an input for the LCA within green certifications, and (3) provide suggestions for developing building models. Building models can be helpful during the design process, but the best results are expected when the specifically described steps are followed. These suggestions aim at improving building models in terms of their usage for green building certifications and particularly for LCA. All the investigated results were clarified and adjusted using a model of a recently finished building in Zug. As reference tools, One Click LCA and a manual process were selected. The outcomes were aligned with those of other studies and confirmed the necessity of good data and management quality for building projects.

Life cycle assessment (LCA) has become an important part of building design optimization. Design studios need tools that make the LCA of buildings faster and simple, and provide results that allow comparison between variants. The objective of this study was to show the possibility of LCA data integration into the existing building design tool, the DEK Building Library, which is already widely used in the Czech Republic, by connecting it to 1200 items of the largest Czech cost-estimating database, and the application of this connection into building information modeling (BIM) tools. This process also included the large-scale adaptation of 160 relevant LCA data. The main result was obtained using EnviBIM, a freely accessible BIM plugin, as well as a web interface that allows users to receive cradle-to-gate environmental impacts of DEK Building Library elements. Additionally, a semi-automated algorithms system for different groups of building materials and elements named EnviDataGenerator was developed in MS Excel, which enables the consistent linking of LCA data to the cost-estimating database items. This allows EnviBIM extensions and upgrades. The EnviBIM module was validated using case studies of three buildings modeled in ArchiCAD and REVIT. The difference in results compared to the manual calculation was 3.1% to 10.9%, which was considered a success.