Crime Prevention Through Environmental Design or CPTED (pronounced sep-ted) as it’s come to be known is fundamentally based upon the theory and belief that: the proper design and effective use of the built environment can lead to a reduction in the incidence and fear of crime, and an improvement in the quality of life.
CPTED’s underlying objective is to help various disciplines do a better job of achieving their primary objectives, with the added by-product of improved security and loss prevention. This objective is based upon the belief that crime and loss is a by-product of human functions that are not working.
The concept of natural surveillance was first identified by Oscar Newman as one of four requirements needed for the establishment of Defensible Space. Natural surveillance is a design strategy that is directed at keeping intruders under observation. It is based on a simple premise that a person inclined to engage in criminality will be less likely to act on their impulse if he or she can be seen.
Natural surveillance is commonly associated with the establishment of clear sightlines. While generally a worthwhile goal, the pursuit of clear sightlines must be tempered by a number of considerations including the ability to capitalize and/or generate witness potential and the need to establish and provide for landscaping.
Successful natural surveillance applications include:
- orienting driveways and paths towards natural forms of surveillance such as building entrances and windows
- increasing visual permeability of vulnerable areas such as building entrances, stairwells, playgrounds etc. through the strategic use of windows, fencing material , landscaping etc.,
- trimming back overgrown landscaping,
- strategically lighting pathways and other potentially problematic areas where opportunities for natural surveillance exist, and
- developing uses for the environment that are capable of strategically generating activity. This can include the establishment of sidewalk patios, seating areas and other amenities
Natural surveillance can be complemented by mechanical forms of surveillance (closed circuit television) and/or organized forms such as security and police patrols. Mechanical and organized forms of surveillance should be emphasized where natural forms of surveillance are limited. This includes parking garages and any place that regularly lacks a critical intensity of people.
Natural Control Access
Natural access control is a design concept that is directed at decreasing crime opportunity. It is based on the simple premise that a person who is confronted with a clearly defined and/or strategically developed boundary, will typically show it some deference by respecting the way it guides and influences their movement as they transition from public through private space. Natural forms of access control includes fences, low walls, landscaping, gates and any barrier that is natural for the environment including topographical features, sales counters and even distance. Natural forms of access control are particularly effective when combined with natural surveillance. The combination of natural forms of surveillance and access control can create a perception of risk in offenders that reduces their desire to step foot on the property or engage in criminal activity.
Successful natural access control applications include:
- providing clear border definition of controlled space
- limiting uncontrolled and/or unobserved access onto properties, buildings and private space
- adding dense or thorny landscaping as a natural barrier to reinforce fences and discourage unwanted entry
- using space to provide natural barriers to conflicting activities.
Natural access control can be complemented by mechanical forms of access control such as locks and alarms and/or organized forms such as security and police patrols. Mechanical and organized forms of access control should be emphasized where natural forms are limited. This includes compounds, storage areas and any place where that regularly lacks people.
Territorial Reinforcement has its’ roots in Oscar Newman’s Defensible Space. It is a design concept that realizes that physical design can create or extend a sphere of influence so that users develop a sense of proprietorship that is noticeable to the offender.
Territorial reinforcement has been described as an umbrella strategy that encompasses natural surveillance and access control. Used properly, natural surveillance and access control can help people to develop a sense of ownership about a space regardless of whether or not they own it. Territoriality often results in challenging behaviour.
Successful territorial reinforcement applications include:
- creating clearly marked transitional zones as persons move from public to semi-public and private space using paving patterns, symbolic barriers or markers, signs and other visual cues
- providing amenities in communal area that encourages activity and use
- avoiding the creation of no-man’s land by ensuring that all space is assigned a clear, and preferably, active purpose
- developing visitor reporting procedures for larger scale entities that regularly receive people
- conducting timely maintenance
Second Generation Principles
The environment can affect behaviour but it cannot create community. It is the strength of the social interactions within a community the ultimately create safe environments.
Second Generation CPTED produces a holistic understanding of a physical environment and the people who use it by emphasizing the strength of the community fabric.
A socially-cohesive community is one where residents and visitors participate in community life, have a sense of responsibility and decision-making within their neighbourhood, and seek methods of conflict resolution. The physical environment can support these interpersonal dynamics by considering how people use and experience a space and participate in activities together. Environments designed to accommodate restorative practice, community markets, workshops, festivals, social organizations and placemaking projects provide the means for neighbours to build relationships within the local and broader community.
Drawing from social ecology, this principle pertains to land-use, scale/size, density, diversity (socially, culturally and in land uses), and available resources (economic, natural, common facilities etc.) Too little of one element or too much of another affects Threshold Capacity. For example, too many bars or nightclubs might destabilise a community and contribute to excessive amounts of fear. Land use diversity provides the necessary conditions to support wellness, sustainable social and physical environments, multiple community interests and positive social interactions.
Communities so not exist in a vacuum. Connectivity addresses the ability of communities to create relationships with external support networks, ultimately strengthening the options available to solve local problems and influence municipal planning and development-related decisions. It can also include physical infrastructure such as access to community spaces, walking and bike pathways, transit and green spaces.
Communities of well-being, have a positive sense of identity and pride. There is a sense of place, a shared history, as well as commemorative of significant neighborhood events or people. Placemaking through street art, festivals, and the arts are ways that community culture is developed and celebrated. Community culture helps to provide the context to apply the First Generation CPTED principles.