The quality of the parking will be an important aspect in terms of the attraction of the retail centre and in encouraging repeat visits. But while there are different criteria for large and small retail car parks, the need for visual clarity and efficiency of use is paramount.

Users will seek to enter and leave with the minimum of delay and without confusion about where they should go to find a vacant space. As pedestrians, they want good access to the nearest retail outlet entrance and a clear marker as to where their vehicle is. This 'wayfinding' is important and becomes more critical as the scale of the car park increases.

The site owner will want efficiency in the design to maximise the number of spaces achieved while avoiding features which detract from the overall usability. The ratio of aisles to parking bays is important as is avoiding cul-de-sacs, tight turns and hindrances to clear sightlines.

Space efficiency - that is, the space/sq m ratio, will determine the number of spaces achieved in the available area and the cost of construction. Aligning the aisles in the longest axis will generate fewer aisles and more spaces, and using full 'bins' - that is, parking bays either side of one aisle - makes the best use of space. Designating 'one-way' travel directions reduces the required aisle width, together with being considered safer than two-way flow.

There is a perception that aisles should be directed towards the shops, however, where this creates aisles in the shorter axis, the number of aisles thus created makes searching for a vacant space more difficult and requires more turns and confusion as well as a net loss in the parking spaces provided. People visiting the site will be aware of the direction of travel from the shops' visual presence and do not need drive aisles to locate them. However, they do need through routes and crossings, which make the whole parking experience far more pleasant and user-friendly.

Where the aisle is wide, it's useful to get pedestrians off the drive aisle for safety and to aid visual clarity with the crossings.

Standard bay sizes are 4.8m long by 2.4m wide - the dimensions found in most town centre car parks. However, an increasing number of prestige retail centres are opting for 2.5m-wide bays to allow easier access and manoeuvrability.

For structural parking the 'bins' should be clear of columns so that parking is as easy as on a surface layout. Therefore, the structure should be to the rear of the parking bay. Vertical access ramps should avoid sharp turns and steep transitions, and should be wide and afford good visibility, with the layout organised to avoid vehicle crossovers or conflict of flow. Good practice guidance can be found in the Car Park Designer's Handbook by J Hill.

For small car parks, attention to detail is important and the development team should avoid cramming in too many spaces, which will slow movement and deter usage, as a higher throughput is of more use than a few more static vehicles. For decked parking in a small footprint, the ramp and aisle arrangements need a considered approach, but beyond a minimum criteria to facilitate a car's 180° turn, sites can always be made to work.

Wayfinding involves the creation of signs, markings and other visual signals to give orientation and direction, and separate sets are needed for motorists and pedestrians. The design should seek to use the minimum number of signs, nevertheless providing clear and direct assistance.

Large car parks need to be segmented into smaller areas, with colour-coded zones or decks in multi-storeys, which will be noted by the motorist as they park and then picked up again as they become pedestrians. Shopping over, motorists then need to be directed quickly and efficiently out of the car park and, if there is a choice, shown the correct route.

Signs for motorists should be based on highway signage for familiarity and pedestrian wayfinding should be consistent with conventional town centre use. Pictorial and colour display signs are easy to read and with limited word use are understandable even to non-English speakers.

Taking time to carefully design a car park will maximise its use and ultimately increase footfall into the shopping centre.

l Steve Vollar is a partner at structural engineering firm Hill Cannon

Printer friendly version

Email this article to a friend