This thesis project revolves around the last days of an abandoned building in decay, facing demolition. It is situated in Värtahamnen, a harbor area in Stockholm. The area is the subject of a major urban planning project in the upcoming decade. In my project my aim is to contemplate this condition of of a building and how to approach and use the ephemerality of architecture and design in the creative process. By extracting different material behaviors caused by decay and exploring them experimentally, a diverse “buffet” of design concepts and methods are presented. The project also orbits around the subject of preservation, a topic commonly debated during interventions in the built heritage. Instead of taking a stand for or against the demolition of the building, the field of experimental preservation is used as a theoretical and methodological background in the design process, as a way to expand the scope on how to navigate and work artistically with preservation. In conclusion, this project tries to revise our perspective on the concept of decay as something destructive and instead suggest the creative potential in understanding it. It also contributes with reflections and speculations on how we can find new creative strategies for taking the whole lifespan of a design project into account already from the beginning.