Purpose: As of today, the knowledge of lean production, and its development into the construction industry, lean construction, has been well described in most of the necessary aspects. In what way lean could affect the work environment in a construction project, be it good or bad, has to date not been thoroughly documented. In Sweden, lean has been mildly tested in the construction industry but the results concerning the effect it has on the work environment is yet to be found in the literature. Lean itself is a strategy for manufacturing processes. The purpose of this study is to contribute to the knowledge of lean itself and how it, theoretically, could affect the work environment at construction site.

Method: To achieve the purpose, documents from the participating company concerning work environment has been analysed in order to visualize what routines the company currently follows. In addition to this, seven interviews were conducted with employees of the company. The persons participating in the interviews were asked about how well they think the work is organized on the construction site right now and furthermore about their thoughts of lean-concept that had been produced, based on the theoretical framework.

Findings: Based on the theoretical framework and findings in the empirical data that has been collected, a lean-concept was developed and refined. The concept includes what routines and what documents that are vital when implicating lean in an effective way, and also what needs to be considered in order not to impede the work environment at the construction site.

Implications: Implicating a well-structured lean-concept in the construction process of a project would, theoretically, most definitely improve effectiveness within the project. It could also improve the work environment of the project, considering the risk awareness and the easier waste-control that the concept could provide. However, it could also make it worse through the elimination of variance and monotonous work tasks that are needed to improve the effectiveness.

Limitations: The most important limitations that the study has had is the fact of it only being a theoretical implication of a lean concept, not a practical case study of the sort. This is due to the defined and limited time that project has had. In addition, the study has also had to limit its’ research to the frame supplement phase of the construction project. This is because of the fact that the work with the theoretical framework and the empirical study would have been too overwhelming, had the study considered the entire production phase of a construction project.