4.7 Cul-de-sacs

Cul-de-sacs reduce an area’s connectivity and usually increase journey distance and times, making walking and cycling less convenient and increasing the private car use.

Cul-de-sacs must not be used except where a site cannot be serviced any other way.

If they must be used, cul-de-sacs should include well-designed, lit, and overlooked pedestrian and cycle links through to neighbouring areas to maintain connectivity.

Where turning heads are required, these can be designed as shared courtyards that can enhance the public realm and include greenery. Please refer to section 5.9 for further guidance.

Where cul-de-sacs already exist, opportunities to improve their connectivity for walking and cycling should be explored.

Figure 4-40: Modal filter removes through traffic, allowing walking and cycling and improving public real (Credit – Create Streets)

The advantages of cul-de-sacs, such as the removal of through traffic, can be achieved on conventional, permeable street patterns using filtered permeability. Modal filters, such as bollards or trees that allow pedestrians, wheelchairs, and cyclists to pass, but not motorised vehicles can be installed on any street. This allows the creation of traditional streets, with consistent frontages and legible, flexible, and efficient layouts, as well as providing opportunities for additional green infrastructure and public space.

Permeability within cul-de-sacs should be greater for active and sustainable modes of travel.

People walking and cycling should be able to move quickly, freely and safely through an area with greater priority than vehicle traffic, linking to the primary and secondary street network.

Figure 4-41: L: A poorly connected street pattern with cul-de-sacs R: A well-connected street pattern (Credit - NMDC)