Background: Digital transformation is an important step in businesses’ quest for environmental sustainability, that changes their business models to create, deliver, and capture value from the use of digital technologies. Another field of research that concerns transformations, is research on socio-technical systems. It explains the adoption of new technologies, by incorporating the social context in which transitions happen. An industry that has been notoriously blamed for being conservative and having sustainability concerns, is the construction industry. Purpose: The purpose of this study was to contribute to socio-technical systems theory, by investigating how interactions in the socio-technical regime can help digitally transform established construction companies and make them more environmentally sustainable. Method: A qualitative case study was performed around Smart Built Environment, a strategic innovation program. From the program, nine reports were examined, and four employees were interviewed. Furthermore, three interviews were conducted with employees of three large construction companies, which were part of Smart Built Environment’s projects. The reports and interviews were used to develop a theoretical framework, which was constructed from existing literature on socio-technical systems, business models, and digital transformation. Conclusion: The results show that culture and habits, and policy and regulations in the regimes have the greatest influence on the digital transformation of construction companies. This is because they influence the relationships between the construction companies and other actors in the construction value chain. Changes to business models that were identified to facilitate the digital transformation were long-term collaborations, product-based development, co-creation, and using digital technologies as a use case for sustainability.