Nowadays the urge of building sustainable is obvious. It is necessary to come up with new solutions in order to give the planet to next generations. It is also known that buildings play a crucial role in this. This will be substantiated in the first chapter of this report. On the other hand, transformation of cities and buildings is one of the main emergent themes in contemporary architecture. Finding an appropriate balance between the old and the new is of fundamental interest for contemporary architectural design (Studio Heritage & Architecture, 2016). Looking at these trends, it could be expected that also a flourishing integration of both takes place. But the opposite is true. When new buildings can be built sustainable but the demand is in the existing stock, the world will be left empty handed. That is the reason the problem statement in this project is: Transformation and sustainability are rarely being combined in contemporary architecture. Fenix II is one of the existing building complexes and located at the south side of the Rijnhaven. Temporary functions created on the short term a new life for the Fenix II. Now a plan is needed for the further development of the old warehouse. Fenix II is on the edge between history and future en thereby an interesting object for this graduation project. Considering the problem statement and object of this project, the aim of this design project is to transform the building into a sustainable building while maintaining the identity and underscore its characteristics. So the design question dealt with is: How to transform the Fenix II into a sustainable building while conserving its characteristics? From the research appeared that Fenix II has a high cultural historical value from which isn't much left in the current situation. On the other hand turned out that the purpose with regard to sustainability was to try to close the cycles of energy, water, material and food within the scoop of the project. Energy became the guiding theme of the design. The ambition is to give back and create energy in the appearance of the building, in its function and operation. The conclusion is that this design shows that it is possible to transform the Fenix II into a sustainable building and conserving its characteristics. Al together, Fenix II will be an energizing warehouse for the inhabitants of Katendrecht and the city of Rotterdam.