To deepen the understanding of the sociotechnical regime that directs the selection of structural frames in multifamily buildings in Sweden, we study the perceptions of contractor representatives. Contract managers (CMs) employed at contractor firms were interviewed regarding their role, the selection of the structural frame and how they perceived different options. The results show that CMs largely influence the selection of the structural frame in multifamily buildings, which are guided by the established concrete-based sociotechnical regime. The regime is maintained through cognitive rules regarding structural frame options and the alignment of skills of construction professionals. Because of their influence and their investments in the skills of construction workers, CMs make important contributions to maintain the regime and the concrete path dependency. Furthermore, the regime varies in strength in different locations. Some locations carry a strong norm to cast concrete frames on site. This makes it more difficult to deviate from the established practice. In other locations, wood-promoting initiatives have changed the cognitive rules associated with the regime. Nonetheless, the sociotechnical regime makes the selection of concrete structural frames beneficial. This prevents wood-framed multifamily buildings from entering common usage, even though such buildings can contribute to mitigating climate change.