Crime prevention through environmental design (CPTED)

Research shows that building design affects whether or not criminals decide to commit a crime. Criminals are more concerned with the risk of being caught than by the rewards they might gain if they commit a crime. So the design of the built environment can help to prevent crime.

There are 3 strategies that can help to reduce crime:

1. Natural surveillance: Increasing the perception that criminals can be seen

• Place windows overlooking pavements and car parks
• Leave window shades and blinds open
• Locate on a busy road with traffic passing regularly
• Use the shortest and most transparent fence appropriate for the situation
• Use transparent weather vestibules at building entrances
• Avoid poorly placed lights that create ‘blind-spots'
• Potential problem areas should be well lit, e.g. pathways, stairs, entrances/exits, children's play areas, dumpster and recycling areas
• Avoid security lighting that is too bright – it can create deep shadows and a blinding glare
• Lighting along pathways and other pedestrian-use areas should be at proper heights for lighting the faces of the people in the space (and to identify the faces of potential attackers)

2. Natural access control: Clearly differentiate between public and private space, by placing entrances and exits, fencing and lighting

• Use a single, clearly identifiable point of entry
• Make sure visitors are directed straight towards reception areas and can't access other parts of the building
• Use maze entrances to public bathrooms rather than anterooms, which can cause isolation
• Use low, thorny bushes beneath ground level windows
• Don't allow access to roofs and upper levels
• In residential properties, use waist-level picket style fencing to control access and encourage surveillance. Your neighbours can clearly see if someone is intruding past your fence
• Use a locking gate to prevent access to back gardens from the front of a house
• Use fairly transparent, shoulder-level fencing between neighbouring gardens. The ability for a neighbour to see into your garden will deter criminals
• Use substantial high, closed fencing, e.g. masonry, between your back garden and a public alleyway

3. Natural territorial reinforcement: Create a sense of ownership of spaces. Owners have a vested interest and are more likely to challenge intruders.

• Keep premises maintained well and gardens landscaped to suggest an active presence in the space
• Provide trees in residential areas. Outdoor residential spaces with more trees are seen as significantly more attractive, more safe and more likely to be used than similar spaces without trees
• Display security system signs at access points
• Avoid cyclone fencing and razor-wire fence topping, as this suggests the absence of people and makes potential intruders think that the risk of being caught is lower
• Placing amenities such as seating or refreshments in common areas encourages people to use common spaces, so keeping criminals away
• Scheduling activities in common areas attracts more people and increases the perception that these areas are being watched and managed