The BIM4LCA project developed guidance for transferring data from BIM tools to LCA tools. The possible pathways for BIM data to LCA have been described in previous chapters. This guidance focuses on the phase from data extraction from IFC to open format. The process of transferring data from BIM tools consists of the steps presented below.
In the BIM tool, select and sort the data required for the LCA. The information to be extracted from IFC has been described in previous chapters; however, the quantity information and identifiable information, such as building element and component type, shall be included in the information take-off (ITO). ITO features are part of BIM tools, enabling information take-off from the BIM model.
In the ITO, data is extracted from the BIM model to be used in other tools, such as LCA tools. This data is typically enriched with data from external sources, as described in previous chapters, and may require an intermediate stage in a spreadsheet editor. Information enrichment is an important part of the data transfer process from BIM to LCA. The data is extracted from the BIM in an open format, which enables the processing of the data and necessary modifications to easily import the data to the wanted LCA tool. When importing data to LCA tools, the LCA expert should ensure that all information from the ITO is imported correctly to the LCA tool to ensure the assessment's quality.
When information has been extracted from the BIM to open format, the LCA expert must supplement the data with information from other sources. Typical sources for supplementing information, as described in a previous chapter, are architectural and structural design documents, and building services design documents. Other typical sources are energy reports and design documents featuring information such as the building’s energy consumption and energy sources. Integration with emission databases happens in the chosen LCA tool. It is recommended that quality assurance of information is done for data imported to LCA tools.
Six-step checklist for transferring data from BIM tools to LCA tools:
Identify the data required: Select and sort data that is required for the LCA
Export data from the BIM tool: Generate an information take-off (ITO)
Supplement the data with information from external sources, such as design documents.
Import data into the chosen LCA tool
Verify data accuracy: Perform quality assurance
Perform LCA analysis using the imported data.