n older days there were no clearly defined limits between private space and public space. People of various social classes live in the same premises. They will separate in the XVIII th century. A classe of owners then develops. They build tenement-houses which they let to the lower-classes, crowding them as much as they can to make the biggest profits of them. Only at the beginning of the XX th century will measures be taken in Parliament to improve the hou sing conditions. Nowadays the surface of our living space is comfortable. And a new need for quality emerges, aiming to appropriation of that living space by personalising it.