Crime Prevention Through Environmental Design (CPTED)
Information for Developers and Municipal Planners
The use of crime prevention techniques in the urban design process has become essential to ensure safe urban environments in present day society. Environmental criminologists have used their theories in conjunction with police in British Columbia trained in crime analysis and prevention techniques. The result is a powerful new tool for urban safety initiatives.
Terms of Reference
- Proposals which come under normal Design Panel review excluding single family units, duplex units and multi-family residential developments under six units. At present, we attend the Advisory Design Panel, Delta Advisory Planning Commission and Development Review Committee meetings, if available, and liaise with the Community Services Advisory Committee
- Rezoning and building permit applications for new buildings, including alterations to exterior designs.
- Applications for extensions of buildings, including alterations to exterior designs.
Territorial Reinforcement
Increase areas perceived as semi-private by extending areas of influence. For example:
- Provide physical and/or psychological barriers around conclaves to deter intruders and encourage ownership by residents
- Utilize vehicular and pedestrian traffic patterns to demarcate borders strongly
- Centralize similar activities to discourage conflicts between different user groups
- Utilize appropriate signage to reinforce territorial ownership
Target Hardening and Access Control
- Locking systems
- Alarm systems and pre-wiring where applicable
- Electronic surveillance systems where applicable
Surveillance
- Cluster dwelling units in such a way to create neighbour-to-neighbour surveillance.
- Utilize oblique angles in facing windows at units adjoining each other to eliminate or decrease any sense of loss of privacy
- Consider eventual planting and landscaping in building design to allow clear, unobstructed views of surrounding areas
- Place high-risk features such as hallways, entries and potential crime targets in areas with the highest potential for observation
- In interior plan design, put high-use rooms on exterior walls with adequate window coverage
Design Considerations
All building design and site planning should be analyzed from the point of view of building security and the inhabitants' safety. Building designs maximizing resident surveillance and minimizing potential trespassing are highly recommended.
Design features to consider include:
- Prominent building entries visible from fronting streets and adjacent dwelling units
- Gated walkways, or large visible unobstructed walkways discourage trespassing and alleviate fear of crime
- Proper lighting at entries, walkways and landscaped areas (in keeping with IES standards)
- Weather protection and special access areas for wheelchairs placed in high visibility areas
- Key control entrances and car park control gates used where applicable.
Parking
New parking safety by-laws should be incorporated in municipal building by-laws where possible, to address security of residents and vehicles, and include:
- Entrances to the parking garage located in areas visible from nearby habitable room windows
- Driveway should provide unobstructed view of passing pedestrians and vehicles where they intersect the roadway
- Driveway ramps having a slope greater than 5% (1:20) should have a 10 foot flat surface before it cuts roadway to improve the sight line
- Surface parking should be located in areas visible to adjoining residents.
Landscaping
Existing prominent landscaping such as mature trees and low hedges should be maintained wherever possible. New plant and landscaping should be shown on landscape plan with safety and security considerations. All landscaping and amenity areas should balance opportunities for mutual observation with privacy considerations so as to err on the side of urban safety for residents, including:
- Discouraging tall evergreen trees at entrances which provide places of concealment. Where evergreen conifers are desirable, lower limbs should be trimmed
- Landscape plans are incomplete without reference to lighting for nocturnal use, safety and security
- Minimum eight feet clearance from ground be considered to allow surveillance through boulevard trees near vehicular traffic areas.
Lighting
Light considerations should take into account the illumination of facilities in the following areas:
- Adequate lighting for all areas of parking lots (especially covered or underground lots). Diffuse lighting patterns that avoid dark spots and bright paints on adjacent walls can help to increase light reflectivity and enhance observability
- Avoid light glare in parks and walkways. These create blind spots when pedestrians walk through them
- Entrances, hallways and corridors should be well lit to provide enhanced territoriality and adequate surveillance
- Underground lighting should utilize vandal-resistant fixtures and maintain a minimum five lux level of colour-corrected lighting for maximum efficiency (refer to CMHC guidelines in their Parking Advisory document)
- Portal lighting should be provided inside all parking garages entrances.
Play Areas
- Play areas should be situated in areas easily observed by the residential units in which they reside, as opposed to being centrally located away from suitable supervision.
- Play areas should be clearly designated and recognized as such.
- Play area fencing should be chain link to provide good visibility.
Fencing
- Fencing strictly utilized for property line distinction should be carefully considered.
- Open-plan site designs and building clustering may alleviate perceived fencing needs.
- For example, necessary fencing should take into consideration possible opportunities for observation by neighbours and designed with urban safety in mind.
Recommended Planning Review Process
Ideally, police officers trained in Crime Prevention Through Environmental Design should consult in municipal planning throughout the process of all proposals. Officers trained in crime prevention can be substituted where properly trained officers are not available.
A cooperative multi-disciplinary group consisting of planners, architects, developers, citizens, landscape architects, police and elected officials all have a role to play in the urban planning process.
CPTED considerations should be consistently included in the plan checking process, Advisory Design Panel, Development Review Committee, Advisory Planning Commission, etc., to ensure the final structure complies and does not conflict with the surrounding land uses. Trained police officers should participate at all levels of the planning process.
References
Brantingham, Paul J. and Patricia L. (1981). Environmental Criminology, Beverly Hills, California: Sage Publications Inc.
Jeffery, C.R. (1971). Crime Prevention Through Environmental Design, Beverly Hills, California: Sage Publications Inc.
Mayhew P. Clarke, R. and Hough, J.M. (1980). Designing Out Crime, London: HMSO
Poyner, B. (1983). Design Against Crime - Beyond Defensible Space, London: Butterworths
Acknowledgments
The Planning Division of the City of North Vancouver, entitled "Advisory Design Panel - General Information and Criteria".
Mr. Gregory Saville, B.A., M.Ed., Simon Fraser University
Glossary
CPTED - Crime Prevention Through Environmental Design is a model for deterring or preventing crime developed by Dr. C. Ray Jeffery, Professor Criminology at Florida State University in 1971. This model operates on the concept that individuals exist who are motivated to commit crimes should the opportunity to do so occur.
CPTED Strategies - There are three basic overlapping strategies: Access Control; Surveillance; and Territorial Reinforcement.
Access Control - Increases the perception of risk to potential offenders and reduces mobility for a crime to be carried out. These measures include denying access to a potential crime target through crime prevention training programs, guards, established security procedures, locks, alarms, lighting, and even landscaping.
Surveillance - Reduces the opportunity for a crime to occur and increases the risk of being seen or identified in the commission of a crime. Surveillance includes measures to ensure visibility and observation through the use of lighting, mirrors, cameras, unobstructed view, and regular police and security patrols.
Territorial Reinforcement - Creates an area of influence and perception of citizen accessibility and ownership. The potential offender is discouraged by the presence of others. Territorial reinforcement begins with site location. Areas of activity and vehicular traffic are deterrents to potential criminals who do not want to be identified and who want to escape easily.
Crimes of Opportunity - Crimes that occur in public places, business premises, or private property in which the environment makes it convenient for the criminal to carry out the act with limited risks for the criminal.
Environmental Variables - Includes lighting, visibility, escape path and route, warning signs, activity, likelihood to be seen, security measures and surrounding land use.
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