Single-use zoning
Single-use zoning is one in which only one type of use is allowed per zone. Known in North America as "Euclidean zoning" (Euclidean zoning) due to a court case in Euclid "Euclid (Ohio)") (Ohio, United States), which established its constitutionality, Village of Euclid, Ohio v. Ambler Realty Co. 272 U.S.") 365 (1926),[8] has been the dominant zoning system in North America since its first implementation.
Commonly defined single-use zones are classified as residential, mixed residential-commercial, commercial, industrial and space (e.g. power plants, sports complexes), airports, shopping malls, etc.). Each category can have a number of subcategories, for example, within the commercial category there may be separate zones for small retailers, large retailers, office uses, accommodation and others, while industrial can be subdivided into heavy manufacturing, light assembly and warehouse uses. In Germany, each category has a designated limit for emissions. noise (not part of the building code, but the federal emissions code).
In the United States or Canada, for example, residential areas may have the following subcategories:.
Separation between uses is a feature of many planned cities designed before the advent of zoning. A notable example is the city of Adelaide in South Australia, whose city center, along with the suburb of North Adelaide, is surrounded on all sides by a park, Adelaide Park Lands. The park was designed by Colonel William Light in 1836 to physically separate the city center from its suburbs. Low-density residential areas surround the park, providing a pleasant walk between work in the city and family homes outside.
Sir Ebenezer Howard, founder of the garden city movement, named Adelaide as an example of how open green spaces could be used to prevent cities from expanding beyond their boundaries and merging. His design for an ideal city, published in his 1902 book Garden Cities of To-morrow, envisioned separate concentric rings of public buildings, parks, commercial spaces, residential areas and industrial areas, all surrounded by open spaces and farmland. . All commercial activity would be carried out within a single glass-roofed building, an early concept for the modern shopping center inspired by the Crystal Palace.[9].
However, these planned or ideal cities were static designs incorporated into a single master plan. What was missing was a regulatory mechanism that would allow the city to develop over time, establishing guidelines for developers and private citizens on what could be built and where. This occurred in 1916, when New York enacted the first citywide zoning ordinance.[10]
The application of single-use zoning has led to the distinctive shape of many cities in the United States, Canada, Australia and New Zealand, in which a very dense urban core, often containing skyscrapers, is surrounded by low-density residential suburbs, characterized by spacious gardens and tree-lined streets. Some metropolitan areas such as Minneapolis-St Paul, the San Francisco Bay Area and Sydney have several such hubs.
Environmental activists argue that putting everyday uses within walking distance of each other leads to increased traffic, as people have to own cars to live normal lives in which their basic human needs are met, and get into their cars and drive to satisfy their needs throughout the day. Single-use zoning and urban sprawl have also been criticized for making work-family balance more difficult to achieve, as greater distances must be covered to integrate different domains of life.[11] These problems are especially acute in the United States, with its high level of automobile use[12] combined with insufficient or poorly maintained urban rail and subway systems.[13].
Euclidean zoning has been described as functionalist thinking that uses mechanistic principles to conceive of the city as a fixed machine. This conception is opposed to the vision of the city as a living organism or system in continuous evolution, as first defended by the German urban planner Hans Reichow.
Another avenue of criticism of zoning laws comes from libertarians and minarchists who view the restrictions as a violation of people's property rights. With zoning, a property owner may not be able to use their land for the intended purpose. Some economists claim that single-use zoning laws run counter to economic efficiency and hinder development in a free economy, since poor zoning restrictions make it difficult to use a given area more efficiently. Even without zoning restrictions, a landfill, for example, would likely gravitate toward cheaper land and not a residential area. Single-use zoning laws can hinder creative developments like mixed-use buildings and can even stop harmless activities like garage sales.[14].
Mixed-use zoning
Community and planning activist Jane Jacobs wrote extensively about the connections between separation of uses and the failure of urban renewal projects in New York. He advocated for dense mixed-use developments and walkable streets. Unlike villages and towns, where many residents know each other, and low-density outer suburbs that attract few visitors, cities and inner-city areas have the problem of maintaining order among strangers.[15] This order is maintained when, throughout the day and night, there are enough people present with eyes on the street.[15] This can be achieved in successful urban districts that have a great diversity of uses, generating interest and attracting visitors.[15] Jacob's writings, along with growing concerns about urban sprawl, are often attributed to inspiring the New Urbanism movement.
To accommodate the New Urbanism vision of walkable communities that combine cafes, restaurants, offices and residential development in a single area, mixed-use zones have been created within some zoning systems. These still use the basic regulatory mechanisms of zoning, excluding incompatible uses such as heavy industry or sewage farms, while allowing compatible uses such as residential, commercial, and retail activities so that people can live, work, and socialize within a compact geographic area.[16].
Some examples of this are:
Shape-Based Zoning
Form-based zoning does not regulate the type of land use, but rather the form the land use can take. For example, form-based zoning in a dense area may insist on low setbacks, high density, and walkability. Form-based codes (FBC) are designed to respond directly to the physical structure of a community in order to create more walkable and adaptable environments.[20].
The New York Zoning Resolution "Zoning Act of 1916 (New York)") of 1916 also contained elements of form-based zoning. This was a reaction to the Equitable Building (New York), which towered over neighboring residences, decreasing the availability of sunlight. He mandated setbacks for tall buildings that involved a mathematical formula based on height and lot size, and led to the iconic shapes of many early skyscrapers. New York City went on to develop increasingly complex regulations, including floor area ratio, air rights, and other regulations for specific neighborhoods.
The French planning system is primarily form-based; Zoning codes in French cities generally allow many types of uses.[21] The main differences between zones are based on the density of each use on a site. For example, a low-density zone may have the same permitted uses as a high-density zone. However, the proportion of residential uses in the low-density zone would be greater than in the high-density zone for economic rather than regulatory reasons.
The city of Paris has used its zoning system to concentrate high-density office buildings in the La Défense district rather than allowing heritage buildings throughout the city to be demolished to make way for them, as is often the case in London or New York.[22] The construction of the Montparnasse Tower in 1973 sparked protests. For this reason, two years after its completion, the construction of buildings with more than seven floors in the city center was prohibited.[23].