Land has two major utilities: its value of use and its value of exchange. The right to housing, as recognized in a number of international human rights instruments, can be effectively provided by ensuring the use value of land. In the case of housing, this type of use is made up of two constituents: the generic residential condition as derived from the planning use given to land and its specific use as a family home. As housing affordability depends on the changing relationships between house prices and rent, and between house prices and income, one of the main alternatives that has been used to balance the equation, is the financing of the purchase price through the mortgage market. The real estate collapse that began in 2008 is attributable to many factors but two basic issues seem to be at the root of the problem: the mixture of credits of very different qualities in financial products and the lack of reliable information with regard to both the origin of the mortgage and the real estate that guaranteed it. Therefore, in order to maintain the efficiency of the mortgage market as a mechanism to provide affordable housing in conditions of sustainability, it is necessary, with a peremptory nature, to restructure the territorial information systems in such a manner so that they rely on real estate understood not just as the object of rights but also as physical objects that form part of the territory. At the same time, one of the details that must necessarily be included in the content of land information should be the use of a property as a family home, maintaining the circuit with regard to the mortgage chain of family homes permanently identified and isolated within the primary and secondary mortgage markets, both at the time of their constitution and later when the MBSs are issued.