Digitization of buildings requires the systematic handling of a variety and volumes of data. It is a common vision to aim for coordinated homogenization of data structures, enabled by the classification of information. This paper studies the role of building information standards for classification in digitization of the building life cycle. It draws on science and technology studies of information technology standards, big data and building information modelling (BIM) in building research. The approach is based on performativity of standards for information systems, viewing performativity as potentially non-linear and multiple. The five-year design process of a large hospital in Denmark is examined as episodes of performance of the building information standard, particularly one recent standard, the Cuneco Classification System (CCS). The study shows that despite client demands, several building information standards are active over time: an expansive' design brief process adds user demands and uses room classification. Another process diminishes the design brief more than 50%, with several standards in use. The client’s facilities management system, which performs the structuring of data backwards' into the design process, makes architects and engineers (but not contractors) use CCS. This fragmentation of performing standards is denoted multiple performativities' and includes temporal and compartmental performativity.