In the construction sector, projects for building complex structures often exceed estimated costs and time. Therefore, enterprises in this sector rethink and improve their processes. For addressing this challenge, the discipline of Building Information Modeling (BIM) developed new process models to optimize the lifecycle of structures by leveraging technology and data sharing. Recently, enterprises explored the use of IoT technology for generating valid and up-to-date data. In this paper, we present an IoT capabilities map for BIM. This map employs BIM phases and capabilities to provide a structured overview of use cases from the literature and an empirical study we conducted in the rail construction sector. The map helps to guide further research in this area and provides blueprints for companies in the construction industry that seek to make use of IoT for improving their processes.