New forms of data science, including machine learning and data analytics, are enabled by machinereadable information but are not widely deployed in construction. A qualitative study of information flow in three projects using Building Information Modelling (BIM) in the late design and construction phase is used to identify the challenges of codification which limit the application of data science. Despite substantial efforts to codify information with 'Common Data Environment (CDE)' platforms to structure and transfer digital information within and between teams, participants work across multiple media in both structured and unstructured ways.Challenges of codification identified in this paper relate to software usage (interoperability, translation, modelling, and file-based sharing), information sharing (unstructured information, document control, workarounds, process change, and multiple CDEs), and construction process information (loss of constraints and low level of detail). This paper contributes to the current understanding of data science in construction by articulating the codification challenges and their implications for data quality dimensions, such as accuracy, completeness, accessibility, consistency, timeliness, and provenance. It concludes with practical implications for developing and using machine-readable information and directions for research to extract insight from data and support future automation.