The purpose of the article is to define the relationship between property issues and new urban experiences it creates. The article is divided by chapter 3. The first presents the background and urban issues that led to the questioning and, more specifically, the issue of keeping a portfolio of real or virtual way under pressure from the major urban issues. The second part defines the concept of heritage and its representation in a virtual world. We rely heavily on Unesco's work on the preservation of digital data as well as the collective work of Petauque (FR) on the question of meaning to the stored information. Finally, we present the risks of the theory made facing the ground in describing the example of Godin Familistère project that underlies all of our research. It is clear that the article is based on actual experience and is therefore a posteriori looking for experienced face the reality of the Brussels urban governance.