Planopedia

A form-based code is a variety of development regulation that emerged at the end of the 20th century as an alternative to the Euclidean zoning codes that determined most development patterns in the United States throughout the 20th century and into the 21st century. 

While traditional zoning codes focus first on the use of land, form-based codes prioritize the form of buildings, based on the belief that the form of buildings is more important than the use in determining community character. 

Like with Euclidean zoning codes, the purpose of form-based codes is to implement the vision established for a community during a planning process. A form-based code is just an alternative variety of legal tool for implementing a plan.

Form-based codes address the relationship between building facades and the public realm, the form and mass of buildings in relation to one another, and the scale and types of streets and blocks. According to the Form-Based Codes Institute, form-based codes include five main elements: 1) a plan or map of the regulated area designating the locations where different building form standards apply; 2) specifies elements in the public realm, like sidewalks, travel lanes, on-street parking, street trees, and furniture; 3) building standards controlling the features, configurations, and functions of buildings; 4) a clearly defined and streamlined application and project review process; and 5) a glossary to ensure the precise use of technical terms. Other elements can also be included in a form-based code, like architectural, landscaping, signage, and environmental standards.

Form-based codes emerged in the late 20th century in North America as an idea to reform the traditional zoning codes that had encouraged sprawling settlement patterns, with a uniformity of character and negative social and environmental effects, as well as disinvestment in older, struggling communities. Form-based codes focus on the form of buildings and the relationship of buildings to each other and the public specifically to create a stronger sense of community character, and to promote walkability, transit-friendly development, and more compact settlement patterns.

Proponents of the form-based code approach to development regulation trace the lineage of regulations of the formal elements of development back back to Ancient Greece, Ancient China, and Ancient Rome, but the idea gained momentum in contemporary times with the publication of A Pattern Language, by Christopher Alexander. Andres Duany and Elizabeth Plater-Zyberk created the first modern form-based code while planning the development of Seaside, Florida in 1982. Form-based codes are now one of the central tenets of the reform agenda of the large, influential organization known as the Congress for the New Urbanism (CNU).

In recent years, the number of local governments adopting some aspect of form-based coding in their development regulations has increased quickly, according to CNU. For leading examples of form-based codes, CNU points to the Buffalo Green Code and the Lafayette (Kentucky) Downtown Code. Miami 21 and the Denver Zoning Code approved in 2010 are two additional prominent examples of form-based codes.