Environmental Crime Prevention

Crime Prevention Through Environmental Design

What is CPTED?

The term Crime Prevention Through Environmental Design (CPTED) is used to describe a series of physical design characteristics that maximize resident control of criminal behavior within a residential community. A residential environment designed under CPTED guidelines clearly defines all areas as either public, semiprivate, or private. It determines who has the right to be in each space, and allows residents to be confident in responding to any questionable activity or persons within their complex. The same design concepts improve the ability of police to monitor activities within the community. The proper design and effective use of public and private space can lead to a reduction in crime, the fear of crime, reduction in calls for police service and to an increase in the quality of life within a community.

Three CPTED Strategies

Natural Surveillance

Surveillance is a design concept directed primarily at keeping intruders under observation. The primary thrust of a surveillance strategy is to facilitate observation and to accomplish the effect of an increased perception of risk. Surveillance strategies are typically classified as organized (e.g., police, patrol) mechanical (e.g., lighting) and natural (e.g., windows).

Natural Access Control

Access control methods are typically classified as organized (e.g., guards), mechanical (e.g., locks), and natural (e.g., spatial definition). The primary thrust of an access control strategy is to deny access to a crime target and to create a perception of risk to offenders.

Territorial Reinforcement

Physical design can create or extend a sphere of territorial influence so potential offenders perceive that territorial influence. For example: low walls, landscape and paving patterns to clearly define the space around a unit entry as belonging to (and the responsibility of) the residents of that unit.

Design Recommendations

Natural Surveillance / Visual Connection

Provide an opportunity for people engaged in normal everyday activity to observe the space around them. Place activities where persons engaged in those activities so they become part of the natural surveillance system without interruption to their activity. Provide a good "visual connection" between residential and/or commercial units and public environments such as streets, common areas, parks, sidewalks, parking areas and alleys. Place actively used room such as kitchens, living/family room and lobbies to allow for good viewing of parking, streets and/or common areas. Managers, attendants and security personnel should have extensive views of these areas.

Provide for the ability to see into a room or space prior to entering.

Take advantage of mixed use if it exists and provide good "visual connection" between users. This may enable natural surveillance during the day and evening, (i.e., a commercial zone that becomes vacant in the evening or a residential zone that is uninhabited during the day.)

Natural Access / Spatial Definition

Provide clear well-lit paths from the street to the development through all parking and landscape areas, and within the development to building entries. Avoid indistinct walkways and entries where occupants and guest may become lost or disoriented or must search for the correct entry or unit.

Provide adequate lighting, width of path, definition of path and ability to see a destination.

Provide obvious physical security techniques such as locks, lights, walls, and gate and security signs.

CPTED Strategies

Provide clear border definition of controlled space (e.g., fences, hedges, paving patterns and low walls). Avoid unassigned space. As much as possible, all spaces should become the clear responsibility of someone. Provide clearly marked transitional zones that indicate movement from public to semiprivate to private space. For example, the sidewalk represents public space and the main path into a residential development is semiprivate, and a path that branches to an individual unit(s) becomes semiprivate and the interior of the unit becomes private space.

Relocate gather areas to locations that provide natural surveillance and access control, as opposed to locations away from the view of would-be offenders. For example, all play areas should be located within the central common area of the building with as many units as possible able to glance or watch children play.

Place activities in locations where the natural surveillance of these activities will increase the perception of safety for legitimate users and risk for offenders. For example, well-used common areas (safe) may overlook a parking area (unsafe) to provide additional security for the parking area.

Place activities in locations to overcome vulnerability of these activities with natural surveillance and access control of the safe area. For instance, common toilet facilities and laundry rooms should not be located in a remote corner of the site or at the end of a long nameless hallway. Locate these facilities (unsafe) adjacent to the entry or location where there is normally high foot traffic (safe).

Redesign or revamp space to increase the perception or reality of natural surveillance.