CPTED is based on four elements:
NATURAL SURVEILLANCE
Natural Surveillance is a design concept directed primarily at keeping intruders under observation. It utilizes design features to increase the visibility of a property or building. The proper placement and design of windows, lighting, and landscaping increases the ability of those who care to observe intruders as well as regular users, and thus provides the opportunity to challenge inappropriate behavior or report it to the police or the property owner. When natural surveillance is used to its greatest advantage, it maximizes the potential to deter crime by making the offender’s behavior more easily noticeable to a passing individual, police patrol, or private security detail.
Natural Surveillance – The Visual Connection:
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 activity rooms such as kitchens, living/family rooms and lobbies to allow for good viewing of parking, streets and/or common areas. Managers, doormen, attendants, and security personnel should have extensive views of these areas.
NATURAL ACCESS CONTROL
Natural access control employs elements like doors, shrubs, fences, and gates to deny admission to a crime target and to create a perception among offenders that there is a risk in selecting the target. 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. Physical and mechanical means of access control-locks, bars, and alarms can supplement natural access control measures if needed. A fence around a neighborhood playground is an example of an access control measure that protects children from wandering off and inhibits entry of potential offenders.
Natural Access Control – The Spatial Definition:
Locate common areas as centrally as possible or near major circulation paths within the project. Avoid remote locations for common areas.
TERRITORIAL REINFORCEMENT
Territorial reinforcement employs such design elements as sidewalks, landscaping, and porches to help distinguish between public and private areas and helps users exhibit signs of “ownership” that send “hands off” messages to would-be offenders. The concept of territorial reinforcement suggests that physical design can create or extend a sphere of territorial influence and 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 the unit.
Territorial Reinforcement Fosters A Sense Of Ownership:
People take more interest in something they own or when they feel intrinsically involved. Therefore, the environment should be designed to clearly delineate private spaces. Provide obvious defined entries, patios, balconies and terraces. Use low walls, landscape and paving patterns to delineate ownership and responsibility.
MAINTENANCE
Lastly, care and maintenance allows for the continued use of a space for its intended purpose. Deterioration and blight indicate less concern and control by the intended users of a site and indicate a greater tolerance of disorder. Proper maintenance protects the public health, safety and welfare in all existing structures, residential and nonresidential, and on all existing premises by establishing minimum requirements and acceptable standards. Maintenance is the responsibility of the owners, operators and occupants.