Urban planning and regulatory frameworks in most jurisdictions in North America support conventional suburban development. This type of development is characterized by a discrete separation of different kinds of building uses, low building densities and access by automobile.
A by-product of suburban development is a loss of sense of place. Building housing projects does not always make for strong communities. Segregating residential development from all other uses, with the car as the only common denominator, undermines genuine human connections.
Analyzing the effect of regulations on urban development, Charles C. Bohl and Elizabeth Plater-Zyberk have noted how hidden instruments shape the form of the city. Those instruments include engineering standards, building codes, zoning bylaws or ordinances and lenders’ guidelines: all designed to support suburban sprawl.
Efforts to enhance variety and sustainability in built form—socially, environmentally and economically—have frequently been thwarted by standards and codes. To counter the current paradigm, some urban planners have proposed transect planning as a tool for understanding and designing places that feel more like neighborhoods.
Origins of the Transect
Geographer and naturalist Alexander von Humboldt introduced the concept of a transect in the 18th century. Defined as a cross section of a region, Humboldt used it to examine transitions in natural land forms, from shore to wetlands to plains and uplands.
More recently, the Miami-based firm of Duany Plater-Zyberk (DPZ) and Company has deployed the concept of a transect to facilitate place making in cities and regions. The firm has published a guide to the transect’s use entitled SmartCode Manual and founded the Center for Applied Transect Studies.
Beginning with the notion of a holistic framework for community building, a transect encompasses a sequence of environments, from natural setting to urban core. Each area is treated as an ecological zone. This rural to urban transect, as it is called, facilitates place making and provides an alternative basis for planning, regulations and financing of urban development.
Rural to Urban Transect Theory
In the SmartCode Manual, DPZ describes a transect in a human environment as a cross-section that “can be used to identify a set of habitats that vary by their level and intensity of urban character.” This range of habitat can then be used to organize the elements of city-building: building, lot, land use, street, etc.
The rural to urban sect is broken down into six categories:
- T1: Natural zone representing wilderness or land which has reverted back to a natural state.
- T2: Rural zone: sparsely settled, cultivated landscape, including grasslands, woodland, agricultural lands and irrigable deserts.
- T3: Sub-urban zone or hamlet: low density suburban residential areas, characterized by naturalistic planting, deep building setbacks and large blocks.
- T4: General urban zone (similar to concept of village): some mixed use, but mostly residential urban development and a wide range of building types; single house and rowhouse predominate.
- T5: Urban center zone (town or neighborhood unit): higher density mixed-use building types: retail, offices, rowhouses and apartments; a neighborhood unit.
- T6: Urban core zone (quartier in European cities): highest density development, greatest mix of uses and civic buildings; a transit oriented development.
The genius of the rural to urban transect is the way it encompasses a continuum of interrelated environments, with differing densities and opportunities for social interaction. It does not prescribe how variety is achieved in any one region or city, but rather suggests strategies for developing form in cities so that they have a sense of place.
The application of a transect varies from one culture and place to another. Its success in a North American context will depend on its proponents’ ability to create planning tools and regulations that support its use. The SmartCode Manual establishes an alternative framework for guiding this regulatory change.
Andree Iffrig - Andrée Iffrig LEED AP is a writer and award-winning graduate architect. She uses her broad background in environmental design and ...
