DESIGN... Site Framework PROCESS IMPLEMENTATION 22 TOOL DESCRIPTION The neighbourhood unit is a holistic planning and design strategy that addresses the configuration of the major physical components of a community. This includes the land uses, transportation systems, public spaces, and green infrastructure, each of which have a clear place in an organizational hierarchy within a defined area. The configuration of these components in a cohesive manner can help to create synergies among land uses, activate the public realm, and create opportunities for housing and mobility choice. This results in a liveable community with a clear place identity. The neighbourhood unit, as a physical planning concept, was first defined by Clarence Perry for the Regional Plan Association of New York in the 1920s. It has since been refined and updated to accommodate new ideas in planning and urban design; within the last decade, for example, green infrastructure systems have been positioned as an integral component of an environmentally sustainable neighbourhood unit. Typically, the neighbourhood unit is defined by the following characteristics: a mix of uses and building types a range of mobility choices a dynamic relationship between the elements of the public and private realm a clear organizational hierarchy Credit Each of these characteristics is interrelated. As such, this tool is a synthesis of a number of the design and process tools described in this tool box. The following sections describe important considerations in planning a neighbourhood unit; the case studies that follow illustrate how those considerations have been applied. Mixed Uses and Building Types A mix of uses in a neighbourhood provides residents the opportunity to live, work, and find daily needs and services within their community. Mixing uses is not a matter of varying land use on a block-by-block basis, but integrating complementary uses in a range of appropriate building types within a common area. This mix provides a community focal point, which helps to create place identity for the new community. Tool Intent To inform the physical configuration of a neighbourhood to create synergies among land uses, activate the public realm, and create opportunities for housing and mobility choice, all resulting in a community with a clear place identity. USERS Municipal Officials Municipal Planning Staff Planning + Design Professionals Engineers Land Developers Landowners Community Members Credit Duany Plater-Zyberk & Company, Inc. Credit www.bing.com/maps, 2010 Microsoft Corporation
NEIGHBOURHOOD UNIT CONCEPTS Original Neighborhood Unit Concept Clarence Perry, Regional Plan Association, 1929 The 5-minute walking radius is the standard indicator for informing the configuration of and distribution of land uses in a walkable neighbourhood. Ideally, most daily needs of the neighbourhood residents are available within this area. Commercial and community uses are located at important junctions within and on the edges of the neighborhood. Updated Neighborhood Unit Concept Duany Plater-Zyberk & Company The relationship between transit and land use is important. Mixed uses, and higher intensity uses, are concentrated around major junctions and along important thoroughfares - especially around existing (or future potential) public transit stops. These uses are shared with adjacent neighbourhoods; not every neighbourhood may have them or require them if others provide them. 23 Internal streets connect to those in adjacent neighborhoods. Sustainable Neighborhood Unit Concept Farr & Associates, 2008 A multifunctional greenway/open space network can be woven through the site. Non-pipe stormwater management system (rain gardens, pervious pavement plazas, stormwater boulevards) are integrated into the rights-of-way. The greenway/open space network is part of a pedestrian transportation network and provides public recreation spaces.
24 The amount of non-residential use (commercial retail, office, entertainment, etc) varies between communities. Not every new greenfield community will be able to support a mixed-use residential and commercial junction or main street. Depending on the economic and physical contexts, it may be more appropriate for a new community to share commercial uses with adjacent neighbourhoods. Mobility Choices A mix of uses has an important effect on the function of transportation network in a neighbourhood. Mixed uses allow non-vehicular transportation walking and cycling to become viable options for residents. This in turn helps to reduce traffic congestion, as trips that might otherwise be taken by car are either reduced or eliminated. Complete Streets (p.49) facilitate mobility choice in the neighbourhood unit. The 5-minute walking radius is the standard indicator for informing the configuration and distribution of land uses in a walkable neighbourhood. Ideally, most of the daily needs and services in the neighbourhood are a five- to 10-minute walk for most residents. The area accessible represents a walkable catchment (see p.72). This requires that non-residential uses be clustered in a neighbourhood. This cluster should be located around major transportation junctions and/or along important thoroughfares, which, depending on the context, could potentially be shared with neighbouring communities. Defined public and private realm The physical design of the relationship between the private realm (housing, businesses, private outdoor spaces) and the public realm (streets, parks, plazas, greenways) is important if the positive benefits of mixed uses and mobility choices especially for pedestrians are to be realized in a community. This relationship between uses and pedestrian activity is mutual. A mix of uses can stimulate pedestrian activity, activating the public realm, while an activated, pedestrian friendly public realm can make a mix of uses viable. There are several design considerations that impact the definition of the public and private realm: The orientation of buildings relative to the street can affect how the street is used. Pedestrian activity will decline where buildings present blank walls to sidewalks, or where large parking lots are situated between sidewalks and building entrances. Similar building types should face one another across major streets; transitions between substantially different building types ideally occur on back alleys or across side streets. Variation in the intensity and scale of uses and buildings draws a mix of users, at different times of day. To achieve the synergy between pedestrians and uses consider the potential means and frequency of movement between origins and destinations within the neighbourhood unit. A certain minimum proportion of uses is required to stimulate pedestrian activity and to provide economic incentives for developing with mixed-use patterns. The physical relationship between vehicular traffic and pedestrian traffic can affect pedestrian activity. The provision of physical objects that separate pedestrians from traffic, or a complete traffic calming strategy (see p.53) will help to activate the public realm; narrow sidewalks next to busy streets will discourage walking. Organizational Hierarchy A neighbourhood unit is not composed of a homogenous mix of uses and multi-modal transportation connections, but rather is a heterogeneous configuration with a clear organizational hierarchy. Central to the neighbourhood unit are public spaces and mixed use activity centres, which give residents a sense of centrality and a place for congregation. The basic elements of the physical framework the streets and blocks are used to define these public spaces; buildings framing the spaces turn them into outdoor rooms, which may be connected to larger greenway or open space networks. Mixed uses frame the central public spaces. Further from them, but still within walking distance, are quite residential streets. McKenzie Towne, Calgary Credit Stantec Consulting / Carma Developers L.P. Mahogany, Calgary Credit Hopewell Communities Hidden Springs, Idaho, USA Source www.hiddensprings.com
WHEN IN THE PROCESS IT IS USED? The neighbourhood unit is a holistic design concept. As such, it should guide the design process from start to finish, and help to relate community design concepts to the public during the consultation process. CASE STUDIES BEST PRACTICES The following local and international examples illustrate the many different forms the neighbourhood unit can take in greenfield development. MacKenzie Towne, Calgary MacKenzie Towne is composed of four neighbourhood units (three are built-out as of this writing). Developers of MacKenzie Towne aimed to incorporate elements of traditional neighbourhood design while still achieving broad market acceptance. Each unit is within walking distance of a public square. High Street, the core commercial street, is itself a walkable commercial cluster. The relationship between the public and private realm was given careful consideration in planning the community tree-lined sidewalks, the use of a build-to line, and the location of garages at the back of the lot (with alley access) help to make the streets pedestrian-friendly. Mahogany, Calgary This planned greenfield community in southeast Calgary composed of six neighbourhoods, with a transit-oriented commercial centre. Each neighbourhood is organized around a public space, which is connected to others around the site by way of a trail system. Each neighbourhood centre has a local transit stop with a supporting mix of uses, including higher density housing, schools, daycares, local commercial, as well as other suitable transitsupportive uses. Prairie Crossing, Grayslake, Illinois, USA Credit The Liberty Prairie Foundation Hidden Springs, Boise, Idaho, USA Hidden Springs is a greenfield development north of Boise, Idaho. The community contains a mix of commercial and community uses, pedestrian/cycle-friendly streets, and a contextsensitive open space network. By configuring smaller-than-typical suburban lots to create a walkable urban form, space was available to create a recreational open space network. 25 Prairie Crossing, Grayslake, IL, USA Prairie Crossing is a conservation subdivision centered on an innovative, comprehensive stormwater management system. With two small-scale transit-oriented, mixed-use neighbourhood centres, the neighbourhood is uniquely positioned to offer commuter access to Chicago or Milwaukee via each of those city s regional rail systems. A pathway network connects housing clusters to the two neighbourhood centres. Northwest Crossing, Bend, Oregon, USA Credit Urbsworks Inc. Northwest Crossing, Oregon, USA Northwest Crossing draws from the design principles of Bend, Oregon s older neighbourhoods. The community is characterized by a grid of interconnected streets, which makes shops, parks, and schools within an easy walk of most homes. Place identity is lent by the mature trees retained throughout the community, which provide the impression of a mature, well-aged neighbourhood. The Woodlands, Texas, USA The master plan of the Woodlands is an ecologically-driven, seven-village concept, centered on several major commercial and institutional districts and connected by an extensive open space networks. Each village offers a variety of housing types, complemented by schools, recreational facilities, shopping, houses of worship, and community services. Villages are based on several neighbourhood units, many of which include parks, and are linked by a network of trails that connect to schools, shopping, and recreational amenities. The Woodlands, Texas, USA Source http://www.thewoodlands.com/creekside
RELATED TOOLS Transit Ready Planning Residential Street Patterns Complete Streets Greenway and Open Space Networks Block and Lot Standards Walkability Catchment Connectivity Index Walkability Audit Bikeability Audit Form-Based Code Smart Code 26 McKenzie Towne, Calgary Credit ADDITIONAL RESOURCES Barnett, Jonathan. An Introduction to Urban Design. New York: Harper & Row Publishers, 1982. Calthorpe, Peter. The Next American Metropolis: Ecology, Community, and the American Dream. New York: Princeton Architectural Press, 1993. Farr, Douglas. Sustainable Urbanism: Urban Design With Nature. Hoboken, New Jersey: John Wiley & Sons, 2008. Heid, Jim. Greenfield Development Without Sprawl: The Role of Planned Communities. Washington, D.C.: Urban Land Institute, 2004. Katz, Peter. The New Urbanism: Toward an Architecture of Community. New York: McGraw-Hill, Inc., 1994. Northwest Crossing (http://www.terrain.org/unsprawl/18/) Mahogany (http://www.calgaryarea.com/se/mahogany/communitynews/mahogany_community_plan.pdf) Prairie Crossing (http://www.terrain.org/unsprawl/9/)