Abstract

Historically, the European city was mixed (in terms of its use) and dense (in terms of its building structure). With the rising popularity of the body metaphor, the idea of a spatial separation of uses spread. John of Salisbury famously postulated that, just like the body, the city should be separated according to its different functions. The different body parts were connected through veins and arteries, in which traffic, air and water circulated.

This corporeal ideal of city planning through separation and circulation reached its zenith in the 1933 Athens Charter that was heavily influenced by Le Corbusier. According to his blueprint, living should be desuburbanised so as to enable a strict separation of living, working and leisure.

The German Federal Land Utilisation Ordinance (Baunutzungsverordnung – BauNVO) from 1962 was based on this ideal of the separation of uses. As a second pillar, it aimed at the reduction of density. The specific land-use areas defined in the BauNVO established city spaces reserved to functionally defined uses such as living and working. This spatial model came under pressure almost with its implementation. From the very first amendment in 1968 onwards, the separation of uses was softened in favour of mixed-use areas. At the same time, density was increased. In four substantial amendments (1968, 1977, 1990 and 2017), the ideal of a functionally structured city was slowly abandoned; not by name (the BauNVO still distinguishes functionally specific land-use areas), but in fact, because the functional description of the areas was successively extended to comprehend ever more (different) uses. In 2017, a new mixed-use area was introduced into the BauNVO (the so-called urban area) and in 2021 another mixed-use area (the so-called rural living area) is projected to follow.

This development has consequences, most notably regarding the system of legal protection. With the decreasing relevance of specific and specifiable land-use areas, the individual and the disturbances it is subjected to become the main focus of legal protection. Thus, the right to mutual consideration slowly replaces the right of the inhabitant of a functionally separated area that the area’s character be maintained.