Designing lighting systems

When lighting designers are brought into the architectural process early, in dialog and collaborative exchange with the architect, it can result in a more integrated and coordinated lighting design.

By Anne Rainbow Savage, WSP December 21, 2017

Learning objectives:

  • Review several considerations for lighting design approaches and specifying lighting systems.
  • Understand the importance of lighting fixture mock-ups.
  • Assess a case study that highlights a successful lighting design.

Lighting design for architecture is one of the most critical and impactful design components within a building system—though it is a skill that is often underused and improperly applied. Using light as an additive tool to communicate and reinforce an architectural idea—to elicit a feeling within the space—is one of the main goals. By controlling light and shadow, evoking emotion, enhancing the built environment, supporting movement, and activating spaces, we begin to see the benefits of a successful architectural lighting design.

Architectural lighting design is a complicated process that accounts for myriad requirements and conditions. Design considerations include:

  • Most important, how does the lighting impact the human occupants in the space? Does the lighting support the goals of the project?
  • How can functional requirements be met while enhancing the experiential qualities of the space?
  • What kind of activity does the space serve?
  • How much light, and what degree of lighting uniformity, is required for those activities?
  • What materials are used, and how can the color of the light and the color rendering of the source impact those materials?
  • What are the areas/materials being highlighted? Where should light be applied?
  • What is the optimal distribution of the luminaire and source for desired coverage and effect?

In addition to these design considerations, there are a host of technical issues that also need to be addressed in a successful architectural lighting design.

  • What are the recommended industry-standard light levels for the space type?
  • What local and national code requirements must be met within the jurisdiction?
  • What are the special energy, municipal, or space code requirements?
  • What are the hours of operation, and what type of daylight exposure does the space have?
  • What light-source types best support the design and performance criteria?
  • Where can luminaires be mounted, based on the limitations of the architectural envelope and finish palette?
  • What kind of lighting controls are required to achieve the desired balance of light and shadow?
  • What kind of lighting controls are required for building use and occupancy patterns?
  • What is the lighting budget? How can the designer achieve the maximum result for a minimum cost outlay?
  • What is most effective way to coordinate with other disciplines?

What constitutes successful lighting design? Illumination that supports the architecture, activates the space.

Successful design is integrative. Lighting, more than any other kind of design, embodies this. The most beautiful, award-winning lighting projects have thoughtful and interesting architecture, systems, or art pieces. Conversely, these forms lose much of their impact without light to bring them to life. Breathtaking spaces and experiences are the results of a careful dance between form and light. The truth is that lighting, when properly applied, draws the eye. It can enhance simple materials and disassociated volumes, improving even the most mediocre architecture. For the lighting design to sing, to reach the zenith of its impact, it needs structure and material to enhance. The better those items are, the better the overall results.

Light and shadow

Just as light and form need each other, so too do light and shadow. In some cases, what is lit up is often not as important as what remains in darkness. An object or space lit to uniformity becomes flat and loses drama. Imagine an afternoon under a tree or an evening on the beach. These images are so universal and often ingrained in our minds because of the way light and shadow play through the treetops or off the waves. The outlines of the leaves become distinct to the eye as form, light, and shadow come together.

Allow for darkness. The most successful lighting designs are often a blend of the edges where science meets art. One of the most critical aspects of a well-considered lighting design is the balance between light and shadow. Architectural lighting design, much like painting, uses light as a painter might use white—both are additive. Light can bring attention, create patterns, and influence movement. But it is most impactful when paired with its opposite, darkness; chiaroscuro.

Designs that provide harmoniously disparate levels of illumination impact biological, visual, and emotional mechanisms in both animals and humans. The move from daylight to darkness is one of the main triggers for our circadian systems, while dappled light illustrates an emotional connection to the sun and nature. The purposeful use of darkness in lighting designs often provides much-needed visual relief, and the use of varying lighting intensities allows the designer to create a visual hierarchy. Processional lighting schemes with pools of light and dark encourage movement and wayfinding. Low levels of illumination in an otherwise darkened space feel intimate and invite time for pause and reflection. High levels of uniform illumination create a feeling of alertness and focus—suitable for the workspace.

Inspiration for solutions

The challenge: to take the concept of design vision and translate it to the built environment. The design must communicate the idea. Lighting illuminates architectural surfaces and materials. Layers of light articulate a sequential or experiential hierarchy through space. Lighting animates the texture of surfaces. The expression of lighting is entirely dependent upon the architectural finishes and material properties. How dark or light, specular or diffuse, glossy or matte, opaque or transparent? What are the colors and textures? How does light render material? Are we putting light on a surface or grazing light across?

One of the most important tools in a lighting designer’s arsenal is the use of mock-ups. Looking at, touching, and focusing the luminaires being considered for a project solution is critical to successfully vetting a lighting solution. Lighting designers use many calculation tools (AGi32, ElumTools, DIALux, and other software programs) to evaluate the lighting performance of specific luminaires(see Figure 1).

But understanding the lighting effects, mounting configurations, and aiming angles to achieve this performance is often best done in a mock-up installation (see Figure 4). Though some projects have budgets for a full-scale mock-up of complicated architectural spaces and details, many smaller projects do not. Working with rudimentary tools like foam core and paper, the beginnings of most lighting detailing can be started with at least a cursory understanding of the effect and cutoff that can be expected with the installation. This method also allows for a true apples-to-apples comparison of different products that may make the same performance claims. Understanding the fit, finish, and appearance of the mounted luminaire goes a long way in helping the lighting designer to refine their choices and preferences in a desired fixture type.

Environmental graphic design

Lighting coordination with environmental graphic design (EGD) for projects typically lags behind the architectural design schedule. However, it’s essential the lighting is provided where appropriate for the EGD element. The EGD team indicates where graphic elements will be located, and together, we discuss what the appropriate lighting strategy should be for the various elements.

For example, for a large-scale graphic applied to an entire wall, we’d want the even top-to-bottom illumination of wall-wash fixtures. Where graphics are more discreet or need dramatic accentuation, designers would use track head luminaires to spotlight the EGD elements. Where lighting is integral to the EGD element, such as neon or backlit panels, the designer would omit external lighting altogether.

By involving lighting design early in the process, architectural design and coordination with other systems, such as mechanical, electrical, and plumbing (MEP), is enhanced. This is particularly important both with an open ceiling, where all systems are visible, as well as where there are ceiling systems with limited plenum space. Collectively, the building systems can establish a “ceiling sandwich,” or zoning for various systems at different heights, which helps to facilitate clash detection and reduce changes required for clash resolution.

Case study: South Lake Union Office Tower

The South Lake Union Office Tower in the South Lake Union neighborhood of Seattle encompasses approximately 866,000 sq ft of a 37-floor office tower. The owner is a large Seattle-based company. Floors 2 to 5 and 16 are amenity floors. Floors 6 to 15 and 17 to 37 are open offices and support spaces. The lighting design team worked with Interior Architects (IA), the WSP design team for the tenant-improvement spaces of Floors 6 to 37.

Standards: While working with the owner on previous projects, the design team helped to develop a set of “standards”—lighting solutions for typical spaces that are repeated project to project within the tenant-improvement spaces. Typical spaces include open offices; small, medium, and large meeting rooms; audio/video (A/V) meeting rooms; small video-teleconferencing meeting rooms; team rooms; copy/communication; and other back-of-house spaces, such as intermediate-distribution frame (IDF), electrical, and mechanical rooms.

Together with the owner, the WSP team reviewed luminaire samples, and in some cases full mock-ups, for approval of all the standard fixture types. The open-office spaces used a direct/indirect pendant fixture, based on Ledalite Chopstick (30% direct light/70% indirect light) with a wide, even (batwing) distribution. The luminaire layout accommodated a corridor row of full-height partition-shared offices, while the rest of the layout was low partitions and desks. This accommodated future expansion of shared offices as well as layouts with varied-height partitions when floors were reconfigured for specific user groups.

Codes: The Seattle energy code is among the most stringent in the country. The project was submitted under the 2012 Seattle Energy Code, which allows a lighting power density (LPD) of 0.90 W/sq ft for office space. By using integral LED-source fixtures, and LED replacement lamps where applicable in decorative fixtures, the energy consumption for combined tenant-improvement spaces of Floors 2 to 37 was 0.49 W/sq ft. The project received a rebate from Seattle City Light for exceeding savings on energy consumption by a significant margin. The project is also on target to obtain U.S. Green Building Council LEED Gold certification.

Lighting controls: All standard and AV meeting rooms have separate dimming for wall-wash fixtures on various walls, in addition to the direct/indirect pendant fixtures over the meeting-room tables. Large dividable AV rooms have five- and six-scene control panels with scenes for various AV scenarios. Per local code, vacancy sensors (manually on, automatic off) are required in numerous spaces throughout. Open offices and other larger spaces use dimming for fixtures within daylight-harvesting zones. Circulation and open offices are controlled by a building management system timeclock, while smaller spaces have individual controls.

The lighting team had the unusual and fortunate experience to be brought into the design early in the process for the tower floors. The group had weekly lighting design meetings with the IA architectural team, during which every architectural gesture and element was addressed. The team examined how the lighting could not only support the architectural design, but also act as an extension of the design concept. The design for lighting and the design for architecture developed symbiotically and was fully integrated to every detail.

Because the architectural design was so conceptual in nature, the integration and implementation of the lighting design had to be carefully, meticulously detailed and executed for full and legible effect. The lighting design had to convey the concepts; it had to communicate, not just look pretty. See Figures 2 and 3.

Visual and experiential hierarchy: Figure 3 elements overlaid onto large floor plates in large sweeping gestures; the use of angles and curves created a direction toward amenity spaces, such as the kitchenette and breakout spaces. As a culmination of focus into those spaces, the lighting had to support the overall expression of movement while also giving identity to these gathering spaces. On floors where the layers of color transitioned to large elements of perforated metal to define a zone—such as layers of angular and overlapping floating perforated-metal ceilings over the kitchenette or angular perforated-metal enclosure surrounding a breakout area—the lighting forms were simple linear (Pinnacle Edge EX2B with T5 fluorescent lamps, using Lee Filters color gel tube on the indirect lamp and no color on the direct lamp) or drum pendants (Resolute Prosperity pendants) that put saturated colored light onto the perforated-metal elements but white (usable) light onto the task surfaces.

The lighting accentuated the architectural language while still providing light for the visual tasks within those spaces. Luminaires in minimalist forms, such as large-scale arcs of illuminated light (custom fixtures using LED neon, fabricated by Eastbay Lighting), respond as an expression of form that is integral to the concept, rather than as an object within and separate from the space. Likewise, we explored patterns of shadow and reflection for additional “Layer 2” concepts on other floors.

Because the Figure 3 elements crossed a multiplicity of surfaces and materials, we had to explore the design from all angles, through elevations and 3-D modeling. We had to evaluate in-person lighting effects with material samples. In fact, much of the lighting design was developed by experimenting with luminaire samples and finish materials to determine scale, effect, and installation details. For example, by aiming a track head through a mocked-up perforated ceiling panel, we were able to determine the size and pattern of perforation, angle of fixture (to minimize glare), and appropriate mounting height to achieve the desired effect. It also helped to determine, in select areas with intentionally lower light levels, that the shadow pattern was legible through contrast.

The IA team not only brought lighting design early into the process, but they brought in the MEP engineers as well. This allowed for early dialogues in how all systems could best work together, where there was room for flexibility, and where there were steadfast constraints. By being cognizant of the constraints, we could look for creative lighting solutions that adapted to the constraints while still being consistent with the architectural language. Coordination between disciplines was fluid and adaptable between trades so that the final installation of all systems was harmonious and intentional.

Anne Rainbow Savage is a senior lighting designer at WSP. As an award-winning lighting designer and architect, she has brought creative, integrated, and technologically proficient designs to more than 2 million sq ft of tenant-improvement commercial space in Seattle.