Glossary & Dictionary Index


Zoning is a North American term for a system of land-use regulation. The word is derived from the practice of designating permitted uses of land based on mapped zones which separate one part of a community from another. Zoning regulations fall under the police power rights governments may exercise over real property. Theoretically, its primary purpose is to segregate uses that are thought to be incompatible; in practice, zoning is used as a permitting system to prevent new development from harming existing residents or businesses. Zoning is commonly controlled by local governments such as counties or municipalities.

Zoning commonly includes regulation of the kinds of activities which will be acceptable on particular lots (such as open space, residential, agricultural, commercial or industrial), the densities at which those activities can be performed (from low-density housing such as single family homes to high-density such as high-rise apartment buildings), the height of buildings, the amount of space structures may occupy, the location of a building on the lot (setbacks), the proportions of the types of space on a lot (for example, how much landscaped space and how much paved space), and how much parking must be provided.

Most zoning systems have a procedure for granting variances (exceptions to the zoning rules), usually because of some perceived hardship due to the particular nature of the property in question.

Types of residential zones would be R1 for single-family homes, R2 for two-family homes, and R3 for multiple-family homes.

Origins and History of Zoning:

New York City adopted the first zoning regulations to apply city-wide in 1916 as a reaction to construction of The Equitable Building (which still stands at 120 Broadway). The building towered over the neighboring residences, completely covering all available land area within the property boundary, blocking windows of neighboring buildings and diminishing the availability of sunshine for the people in the affected area. These laws, written by a commission headed by Edward Bassett and signed by Mayor John Purroy Mitchel, became the blueprint for zoning in the rest of the country, partly because Bassett headed the group of planning lawyers which wrote The Standard State Zoning Enabling Act that was accepted almost without change by most states. The effect of these zoning regulations on the shape of skyscrapers was famously illustrated by architect and illustrator Hugh Ferriss.

By the late 1920s most of the nation had developed a set of zoning regulations that met the needs of the locality. New York City went on to develop ever more complex set of zoning regulations, including floor-area ratio regulations, air rights and others according to the density-specific needs of the neighborhoods.

Among large cities in the United States, Houston, Texas is unique in having no zoning ordinance. Houston voters have rejected efforts to implement zoning in 1948, 1962 and 1993.

Types of Zoning:

Zoning codes have evolved over the years as urban planning theory has changed, legal constraints have fluctuated, and political priorities have shifted. The various approaches to zoning can be divided into four broad categories: Euclidean, Performance, Incentive, and Design-based.

Euclidean Zoning:

Named for the type of zoning code adopted in the town of Euclid, Ohio, Euclidean zoning codes are by far the most prevalent in the United States, used extensively in small towns and large cities alike. Also known as "Building Block" zoning, Euclidean zoning is characterized by the segregation of land uses into specified geographic districts and dimensional standards stipulating limitations on the magnitude of development activity that is allowed to take place on lots within each type of district. Typical types of land-use districts in Euclidean zoning are: residential (single-family), residential (multi-family), commercial, and industrial. Uses within each district are usually heavily prescribed to exclude other types of uses (residential districts typically disallow commercial or industrial uses). Some "accessory" or "conditional" uses may be allowed in order to accommodate the needs of the primary uses. Dimensional standards apply to any structures built on lots within each zoning district, and typically take the form of setbacks, height limits, minimum lot sizes, lot coverage limits, and other limitations on the building envelope.

The zoning ordinance of Euclid, Ohio was challenged in court by a local land owner on the basis that restricting use of property violated the 14th Amendment of the U.S. Constitution. Though initially ruled unconstitutional by lower courts, the zoning ordinance was upheld by the U.S. Supreme Court in Village of Euclid, Ohio v. Ambler Realty Co. (1926). See below for more information.

Euclidean zoning is preferred by many municipalities due to its relative effectiveness, ease of implementation (one set of explicit, prescriptive rules), long-established legal precedent, and familiarity to planners and design professionals. Euclidean zoning has received heavy criticism, however, for its lack of flexibility and institutionalization of now-outdated planning theory (see below).

Performance Zoning:

Also known as "Effects-based planning", Performance Zoning uses performance-based or goal-oriented criteria to establish review parameters for proposed development projects in any area of a municipality. Performance zoning often utilizes a "points-based" system whereby a property developer can apply credits toward meeting established zoning goals through selecting from a ’menu’ of compliance options (some examples include: mitigation of environmental impacts, providing public amenities, building affordable housing units, etc.). Additional discretionary criteria may also be established as part of the review process.

The appeal of Performance Zoning lies in its high level of flexibility, rationality, transparency and accountability. Performance Zoning avoids the arbitrary nature of the Euclidian approach, and better accommodates market principles and private property rights with environmental protection. However, performance zoning can be extremely difficult to implement and can require a high level of discretionary activity on the part of the supervising authority. For this reason performance zoning has not been widely adopted in the USA, and is usually limited to specific categories within a broader prescriptive code when found. New Zealand’s planning system, however, is grounded in effects-based Performance Zoning under the Resource Management Act 1991.

Incentive Zoning:

First implemented in Chicago and New York City, incentive zoning is intended to provide a reward-based system to encourage development that meets established urban development goals. Typically, a base level of prescriptive limitations on development will be established and an extensive list of incentive criteria will be established for developers to adopt or not at their discretion. A reward scale connected to the incentive criteria provides an enticement for developers to incorporate the desired development criteria into their projects. Common examples include FAR (floor-area-ratio) bonuses for affordable housing provided on-site and height limit bonuses for the inclusion of public amenities on-site. Incentive zoning has become more common throughout the United States during the last 20 years.

Incentive zoning allows for a high degree of flexibility, but can be complex to administer. The more a proposed development takes advantage of incentive criteria, the more closely it has to be reviewed on a discretionary basis. The initial creation of the incentive structure in order to best serve planning priorities can also be challenging and often requires extensive ongoing revision to maintain balance between incentive magnitude and value given to developers.

Design-based Zoning:

Design-based zoning relies on inter-related schedules of rules to be applied to development sites according to both prescriptive and discretionary criteria. These criteria are typically dependent on lot size, location, proximity, and other various site- and use-specific characteristics.

Design-based codes offer considerably more flexibility than Euclidean codes, but can be very complex to create and administer. Design-based codes have not been widely adopted in the United States and are often criticized as overly-constraining and difficult to interpret where they have been used.

One example of a recently adopted code with design-based features is the Land Development Code adopted by Louisville, Kentucky in 2003. This zoning code created "form districts" for Louisville Metro. Each form district was intended to recognize that some areas of the city were suburban in nature, and some urban. Building setbacks, heights and design features vary according to the form district. As an example, in a "traditional neighborhood" form district, a maximum setback might be 15 feet from the property line, while in a suburban "neighborhood" there might be no maximum setback at all.

Constitutional Challenges:

There have been notable legal challenges to zoning regulations. In 1926 the United States Supreme Court upheld zoning as a right of U.S. states (typically via their cities and counties) to impose on landowners. The case was Village of Euclid, Ohio v. Ambler Realty Co. (often shortened to Euclid v. Ambler), 272 U.S. 365 (1926). The village had zoned an area of land held by Ambler Realty as a residential neighborhood. Ambler argued that it would lose money because if the land could be leased to industrial users it would have netted a great deal more money than as a residential area. Euclid won, and a precedent was set favorable to local enforcement of zoning laws.

The Euclid case was a facial challenge, meaning that the entire scheme of regulation was argued to be unconstitutional under any set of circumstances. The United States Supreme Court justified the ordinance saying that a community may enact reasonable laws to keep the pig out of the parlor, even if pigs may not be prohibited from the entire community.

Since the Euclid case, there have been no more facial challenges to the general scheme. Beginning in 1987, several United States Supreme Court cases ruled against land use regulations as being a taking requiring just compensation pursuant to the Fifth Amendment to the Constitution. First English Evangelical Lutheran Church v. Los Angeles County ruled that even a temporary taking may require compensation. Nollan v. California Coastal Commission ruled that permit conditions that fail to substantially advance the agency’s authorized purposes require compensation. Lucas v. South Carolina Coastal Council ruled that numerous environmental concerns were not sufficient to deny all development without compensation. Dolan v. City of Tigard ruled that conditions of a permit must be roughly proportional to the impacts of the proposed new development. Palazzolo v. Rhode Island ruled property rights are not diminished by unconstitutional laws that exist without challenge at the time the complaining property owner acquired title.

However, the landowner victories have been mostly limited to the U.S. Supreme Court despite that Court’s purported overriding authority. Each decision in favor of the landowner is based on the facts of the particular case, so that regulatory takings rulings in favor of landowners are little more than a landowners’ mirage. Even the trend of the U.S. Supreme Court may now have reversed with the 2002 ruling in Tahoe-Sierra Preservation Council, Inc. v. Tahoe Regional Planning Agency. Justice Sandra Day O’Connor, who had previously ruled with a 5-4 majority in favor of the landowner, switched sides to favor the government that had delayed development for more than 20 years because of the government’s own indecision about alleged concerns to the water quality of Lake Tahoe.

Specific zoning laws have been overturned in some other U.S. cases where the laws were not applied evenly (violating equal protection) or were considered to violate free speech. In the Atlanta suburb of Roswell, Georgia, an ordinance banning billboards was overturned in court on such grounds. It has been deemed that a municipality’s sign ordinance must be content neutral with regard to the regulation of signage. The City of Roswell, Georgia has now institued a sign ordinance that regulates signage based strictly on dimensional and aesthetic codes, rather than an interpretation of a sign’s content (i.e. use of colors, lettering, etc.).

On other occasions, religious institutions sought to circumvent zoning laws, citing the Religious Freedom Restoration Act of 1993 (RFRA). The Supreme Court eventually overturned RFRA in just such a case, City of Boerne v. Flores 521 U.S. 507 (1997). However, Congress enacted the Religious Land Use and Institutionalized Persons Act (RLUIPA) in 2000 in an effort to correct the constitutionally objectionable problems of the RFRA. In the 2005 case of Cutter v. Wilkinson, the United States Supreme Court held RLUIPA to be constitutional.

Some Limitations and Criticisms of Zoning:

Land-use zoning is considered by some to be an important tool in the treatment of certain social ills, a part of the larger concept of social engineering. Criticism of zoning is widespread, however, and its effectiveness as a tool for positive social change is debatable.


Existing development in a community is generally not affected by the new zoning laws because it is "grandfathered" (or legally non-conforming), meaning the prior development is exempt from compliance. Consequently, zoning can only affect new development in a growing community. In addition, if undeveloped land is zoned to allow development, that land becomes relatively expensive, causing developers to seek land that is not zoned for development, and then seek rezoning of that land themselves. Communities generally react by not zoning undeveloped land to allow development until a developer requests rezoning and presents a suitable plan. Development under this practice appears to be piecemeal and uncoordinated. Communities try to influence the timing of development by government expenditures for new streets, sewers and utilities usually desired for modern developments. However, the development of interstate freeways for purposes unrelated to planned community growth, creates an inexorable rush to develop the relatively cheap land near interchanges. Property tax suppression measures such as California Proposition 13 have led many communities to disregard their comprehensive plans and rezone undeveloped land for retail establishments, desperate to capture sales tax revenue.

Aesthetic Criticisms:

More prescriptive zoning codes tend to give rise to a phenomenon known colloquially as "Design by Zoning," or DBZ. Jurisdictions with highly prescriptive zoning codes can force the uniform adoption of (often unintentionally negative) aesthetic qualities in all new construction due to the inflexibility of the zoning ordinances. This can lead to urban environments dominated by apparently nonsensical or awkward building configurations. An example of this has occurred in the application of the increasingly-complex low-rise multi-family residential code in Seattle, Washington.

Social Criticisms:

In more recent times, zoning has been criticized by urban planners and scholars (most notably Jane Jacobs) as a source of new social ills, including the separation of homes from employment and the rise of "car culture." Some communities have begun to encourage development of denser, mixed-use neighborhoods that promote walking and cycling to jobs and shopping. However, a single-family home and car are major parts of the "American Dream" for nuclear families, and zoning laws often reflect this: in some cities, houses that do not have an attached garage are deemed "blighted" and are subject to redevelopment. Movements that disapprove of zoning, such as New Urbanism and Smart Growth, generally try to reconcile these competing demands. New Urbanists in particular try through creative urban design solutions that hark back to 1920s and 1930s practices. Recently, the New Urbanists have also come under attack for the negative aspects of the highly prescriptive nature of their model code proposals.

Exclusionary Zoning:

Zoning has long been criticized as a tool of racial and socio-economic exclusion and segregation, primarily through minimum lot-size requirements and land-use segregation (sometimes referred to as "environmental racism"). Early zoning codes were often explicitly racist. June Manning Thomas provides a survey of the literature concerned with this particular critique of zoning.

Exclusionary practices remain common among suburbs wishing to keep out those deemed socioeconomically or ethnically undesirable: for example, representatives of the city of Barrington Hills, Illinois once told the Real Estate section of the Chicago Tribune that the city’s 5-acre minimum lot size helped to "keep out the riff-raff."

Zoning and Housing Affordability:

Zoning has also been implicated as a primary driving factor in the rapidly accelerating unaffordability of housing in urban areas. According to critics, as much as half of the price paid for housing in some jurisdictions is directly attributable to the hidden costs of restrictive zoning regulation.

Glossary & Dictionary Index