Lighting the Way to Outdoor Safety
Code requirements, energy efficiency and security all important components in the design plan.
What elevates the design of lighting systems for parking lots and parking garages above just code requirements and illuminance calculations? The experience. We have all been in those poorly lit, less-than-safe feeling parking lots, where we can’t wait to get in our car and drive away as fast as we possibly can.
Vehicles are central to many of our everyday experiences, and many of us probably spend more time driving in circles and parking our cars than we’d like to admit. At night, quality lighting is crucial to making these spaces feel safe, accessible, and connected to their surroundings. The application of intentional lighting design solutions can transform a generic parking lot into an integrated component of a placemaking project that addresses energy efficiency, safety, security, and sense of space.
Balancing code and design
Lighting design in parking spaces often begins with energy code requirements and local jurisdictional lighting requirements. Every locale has different requirements and recommendations regarding light levels, wattages, controls, pole heights, fixture styles, and dark sky ordinances. All these components help to define design constraints. However, code compliance should not be the only benchmark for the design solution.
Codes and local jurisdictional requirements are one angle of approach that should be combined with safety, security, and elevated design. The challenge should be to not just meet energy codes but push beyond to develop strategies that focus on the user experience and cohesive design implementation that performs as efficiently as possible. To exceed increasingly stringent energy codes, the industry is constantly developing new technologies and more efficacious luminaires that work to our advantage as designers. Staying in touch with industry developments helps designers find luminaires and control solutions that better suit their needs.
For parking lot or garage lighting, important developments could include glare reduction, more integrated light cutoff strategies, and updated distributions. Controls are an excellent strategy to reduce overall lighting loads, particularly during daylight hours. Individual level and zoned control systems allow clients the flexibility to further reduce their lighting loads, especially during off hours or if the program uses change. Pressure to comply with today’s advancing energy codes could lead to simplification of parking light design strategies.
With efficiency as the primary goal in the one or two luminaire types that meet horizontal lighting requirements, designers should be careful not to over-simplify and lose sight of a more holistic design approach.
Feeling safe and secure
Energy codes and jurisdictional requirements are often limited to lighting power densities, controls, and horizontal illuminance, but many other factors can strengthen the lighting design from a safety and security standpoint. Uniformity and color quality contribute to how safe a parking lot or garage feels. Dark corners or highly varied light levels make it hard for our eyes to adjust and identify objects, which can make users feel uneasy. Luminaires with poor color rendering can be disorienting, such as the orange glow from HID sources commonly used in older parking lots.
Horizontal light, while providing sufficient levels and illuminating the entire surface is important, attention needs to be given to vertical light from a safety standpoint. Vertical light allows for better facial recognition at night and helps to minimize shadowing that can make a space feel unsafe at night. In parking lots, vertical lighting can be achieved by using pedestrian-scale lighting with a vertical component or lighting closer to the ground at walkways.
If the area has dark sky requirements, shielding, lower output luminaires, and indirect lighting can be used to create the vertical lighting effect while limiting light pollution. In parking garages, vertical lighting may mean throwing light on walls and ceilings that bounces back onto faces rather than only downward lighting which causes shadowing and minimizes vertical lighting.
Advanced lighting control solutions, now often code required, can enhance the perception of safety. Individual fixture-level or zoned occupancy sensors can contribute an additional layer of security. Having motion activated light turning on to full brightness serves as a sixth sense, so to speak, alerting that someone is the area and that you are not alone. Having occupancy sensors as a layer of control adds both to the safety and security of a parking area while also reducing energy consumption when vacant. Uniformity, quality of light, vertical light, and layered controls all contribute to creating safety through lighting in parking areas. These factors not only help to make the pedestrian experience safer, but also create better visibility in spaces where vehicles and pedestrians intersect.
Leilani Nelson is a landscape designer and Rachel Fitzgerald is the discipline leader for Stantec. Both are based in Denver.