Light the walls
Articulate architecture. Define space. Shape perception. Enhance comfort.
Light the walls Traditional lighting design focuses on horizontal light levels. Sustainable lighting design emphasizes reducing energy, squeezing light levels as low as they can go. The result can be gloomy environments that serve watts and footcandles, not necessarily architecture and human needs. For years, lighting best practice has recognized the benefits of placing light on walls, including articulating architecture, providing space definition, influencing perception of space, and enhancing visibility and visual comfort. This guide from Litecontrol describes how to apply these techniques to your designs and deliver these benefits to your clients.
Best practices in contemporary lighting design include wall lighting. Green design practices emphasize efficiency. But if efficiency takes precedence over lighting quality, we risk creating highly efficient spaces that people don’t like being in. While efficiency is important, effectiveness is vital to ensure the lighting supports the owner’s organizational goals. In short, good lighting should be energy-effective.
Many traditional designs emphasize direct lighting, which can produce pronounced shadows and a dim atmosphere. Wall lighting combined with high-reflectance surfaces can mitigate these problems by making spaces appear brighter and more spacious—even spaces with low light levels. Wall lighting can improve visibility by raising light levels and enhance visual comfort by increasing uniformity and minimizing glare.
Lobby with Traditional Lighting
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B
Lobby with Wall Lighting Light defines vision. Light shapes perception. In the 1970s, Professor John Flynn created criteria for evaluating the lighting of spaces based on a series of experiments. His seminal work predicts responses that people will tend to have towards various lighting conditions differentiated by horizontal (overhead) vs. vertical (perimeter) emphasis, uniform vs. nonuniform distribution, bright vs. dim light levels, and visually warm vs. cool color tones. Flynn’s experiments used large numbers of subjects to rate their subjective impressions of different lighting scenes on a scale between pleasant or unpleasant, public or private, spacious or confined, relaxed or tense, and visually clear or hazy. Wall lighting promotes impressions of spaces being: pleasant - people prefer light on walls public - wall lighting increases brightness and uniformity spacious - light on walls coupled with uniform lighting on all surfaces tense - high brightness coupled with uniformity implies a high activity level visually clear - by providing peripheral brightness
Top: USGBC Headquarters Washington D.C. see pp 12-13 Above: Harley Ellis Architects see pp 12-13
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Use the right technique to achieve the desired impact.
B
A
C
Wall washing |A
Grazing wash |B
Wall washing is a popular technique for providing spatial definition. As the eye is drawn to brightness, brighter walls draw attention to architecture.
Grazing wash uses linear wall slot luminaires mounted in a continuous run around the ceiling, which achieves the primary function of wall washing while avoiding glare and producing a cleaner ceiling appearance.
Light the wall with a uniform brightness from top to bottom Use linear sources for best uniformity
Light the wall in a smooth wash from top to bottom while avoiding reflected and direct glare
Place the luminaire at a sufficient distance to achieve a wide angle of light striking the wall
Provide a cleaner ceiling appearance with no visible equipment
Avoid glare for people standing near the wall
Create a visually interesting "floating ceiling" effect Reveal wall surface texture if desired by using narrow angles of light
Left to Right: USGBC Headquarters, see p 12, Bartle Hall, Kansas City Convention Center, see p 14, South Shore Hospital, see p 10
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Wall lighting techniques Wall lighting can be accomplished using several simple techniques, which should be matched appropriately to the application to realize the desired lighting effects and associated benefits. Primary techniques include wall washing and grazing wash, both of which can be used to emphasize architecture and distribute soft, uniform light on vertical surfaces. Wall lighting as an area source can serve to provide comfortable lighting in public circulation areas such as lobbies and corridors. And wall lighting can be used to directly illuminate vertical tasks in spaces such as classrooms and conference rooms. For each, key decision points include lamping, luminaire placement, orientation and distribution.
D Wall lighting as area light source |C
Wall lighting for vertical tasks |D
Wall lighting not only draws attention to architecture, it can also be used to illuminate the space. If the walls are highly reflective, they contribute to task light levels, turning the wall into a highly effective area light source.
Wall lighting can be used to directly illuminate vertical tasks such as teaching boards in schools. Light the walls to illuminate vertical tasks with minimal shadows
Light the walls to accentuate architecture and deliver lumens to task surfaces
Provide sufficient vertical light levels for the task
Select luminaires to produce maximum lumens without direct glare
Avoid glare for people standing near the wall
Achieve brightness across the task
Use fluorescent light sources for high efficiency Use high-reflectance non-glossy finishes to reflect light with minimized reflected glare
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Articulate architecture Wall lighting can change the way people perceive architecture and space. Traditional lighting design focuses on lighting the horizontal task plane. Since the eye is attracted to the brightest areas in the field of view, this approach to design emphasizes tasks, not people and architecture. Placing light on walls draws attention to people and architecture, with controlled contrasts used to emphasize points of interest and articulate architectural details. The space interacts with its occupants and stimulates a desired psychological response. With wall lighting, rooms appear brighter and more spacious, connoting a public, businesslike atmosphere.
Horizontal tasks are often not in the field of view. Viewing means vertical. Walls are an occupant’s first impression of a space. Make the right impression. Brightness focuses attention. Wall lighting draws attention to architecture. Research indicates that people prefer to face bright walls. Give them what they want. The eye follows the brightest path. Bright walls can assist with wayfinding. Bright windows can cause glare and be distracting. Use wall lighting to balance the brightness. Use contrast to highlight points of interest and architectural details. Beautify your spaces with light.
A
|A By lighting the walls, a cavelike, gloomy room can be transformed into a bright, spacious environment that is “open for business.”
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Light the walls
Above: Laurence YoungBlood Energy Library Norman OK, Lighting Dynamics, Photography - James Wilson Truman Medical Center Kansas City, KS, Photography - ©mspillers2007 Right: MGH Yawkey Center for Outpatient Care, pp 10-11
B
|B Brightness focuses attention. Wall lighting draws attention to architecture.
|C Viewing means vertical. Wall lighting reveals the spatial form, enabling a space's dominant boundaries to provide a pleasing luminous backdrop to people, objects and activities. C litecontrol.com
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Wall lighting can help people see objects, spaces and each other more clearly.
C Top: MGH Yawkey Center for Outpatient Care, pp 10-11 Above: Robert W. Danforth Lighting Center Charles Mayer Photography
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Light the walls
Pendant Illumination Only
Promote visual comfort Beyond influencing how people perceive a space, placing light on walls can have a big impact on how well people actually see in the space. This technique turns lighter-color, non-glossy wall surfaces into soft, diffuse area sources, producing interreflections that raise light levels, increase visibility and visual comfort, and make spaces appear brighter and more pleasant.
Visual comfort by design. Wall lighting can illuminate spaces by itself or be used to mitigate the negative by-products of direct lighting. Because of its diffuse characteristics, it is ideal for public spaces as well as regularly occupied spaces where people perform demanding visual tasks for long hours each day, such as healthcare facilities, classrooms and offices. Direct glare is minimized as the light source is often concealed. Reflected glare on computer screens is minimized because light is scattered in many directions and on all surfaces in a space, reducing contrast. Putting more light on vertical surfaces increases their visibility and improves facial recognition, ideal for spaces where face-to-face communication is important. Diffuse lighting reduces shadows that can be distracting and can reduce visibility. Diffuse lighting improves uniformity, which in turn reinforces impressions of space, alertness and visual clarity.
Wall/Slot Illumination Only
Here are several tips on how to achieve good wall lighting that improves visibility and visual comfort: Choose lighter-color finishes on walls. White is naturally a good choice, but a number of pastels are available with reflectances of 70% or higher. Choose matte, not glossy finishes. Glossy does not mean bright. It means glare. That goes for ceilings and furniture, too. Save dark colors for accents and floors. Research suggests office workers prefer 20-25 footcandles on vertical partitions. Put light on window walls. This reduces contrast between the window and the wall. In deeper daylighted spaces, put light on rear walls for balanced lighting. Good modeling of objects can be achieved with a 2:1 horizontal-to-vertical ratio of light levels. Maximum to minimum light levels can vary from 3:1 to 5:1 across a smoothly lighted wall.
Both Wall/Slot and Pendant Illumination
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Light the walls healthcare
Lighting the walls promotes comfort and well being
Right: South Shore Hospital Weymouth, MA, Charles Mayer Photography
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Light the walls
Massachusetts General Hospital Yawkey Center for Outpatient Care Boston, MA Planning and Design Architect - Perkins+Will, Inc. Local Architect - Steffian Bradley Architects, Inc. Photography - Anton Grassl
Emphasizing vertical surfaces is especially important in healthcare environments. Wall lighting can be used in almost any public space in a healthcare environment, making these spaces appear brighter, spacious and more comfortable. Using walls as area light sources ensures good visual comfort for staff working long hours, particularly older staff, and avoids direct lighting that can irritate patients being transported on gurneys. The soft, diffuse lighting quality of wall lighting supports a soothing visual environment for patients and their families.
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US Green Building Council Washington, D.C. Architect - Kendall Wilson, Envision Lighting Designers - Clanton and Associates Boulder, CO Photography - Eric Laignel
Above: Harley Ellis Architects Southfield, MI Photography - Balthazar Korab Ltd.
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Light the walls
Light the walls offices Lighting the walls promotes a businesslike atmosphere
In office buildings, wall lighting can provide benefits in workspaces such as open offices and larger private offices, transition spaces such as corridors, public spaces such as lobbies and cafeterias, and multi-purpose spaces such as conference rooms. Wall lighting makes otherwise drab workspaces appear brighter and more spacious, while increasing uniformity and promoting a public, businesslike atmosphere. These effects are particularly important when lighting is being minimized to save energy.
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Light the walls public spaces Lighting the walls promotes social interaction
Bartle Hall, Kansas City Convention Center Kansas City, MO Lighting Design - Derek Porter Studio Photography - Šmspillers2007
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Light the walls
Public spaces in buildings are places where people move, gather, observe. As a result, they are spaces where architecture and aesthetics are emphasized to communicate visual information about a building and the organization and people that occupy it. Wall lighting in public spaces goes beyond the traditional approach of lighting the floor to delineate and beautify architecture by drawing attention to vertical surfaces. It also enhances identification and social interaction between people, making these spaces comfortable for gathering and conversation, not just transition.
Left: Richmond Airport Richmond, VA, Architect - Gresham Smith & Partners, Photography - Chris Cunningham Above: San Francisco International Airport San Francisco, CA SOM Architects, Photography - Timothy Hursley
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Wall/Slot 2000 The Wall/Slot 2000 perimeter lighting system provides a continuous lighted slot at the ceiling and the wall. The lamps are completely hidden from view, even when directly beneath the luminaire. An innovative optical system minimizes socket shadows and produces a clean line of light at the perimeter of the space. U.S.Patent No. D329,299
2000 13 1/2" (343)
10 1/2" (267)
9" (229 mm)
Ceiling
Design elements Continuous wall lighting, even around corners T8, T5, T5HO or CFL lamping Parabolic reflector option boosts light down wall Easy installation onto wall-mounting rail System connectors allow continuous slot around a room, even around corners Luminance Control Deflector minimizes socket shadows Cradle to Cradle Silver CertifiedCM
SILV ER
No visible hardware
Easy hook-and-lock system
Size comparison
Wall 2000
Ceiling Plane
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2100
Light with
Concealed Lamps
Wall/Slot 2100 The Wall/Slot 2100 system provides perimeter lighting from a small-scale profile, with the lamps completely hidden from view. The 6" height of the luminaire works well in spaces with restricted plenum depths, and the 6" width provides a narrower slot than other fluorescent Wall/Slot products. No lamps or lenses are visible in the 2100 luminaire.
2100
6" (152)
6" (152 mm)
Ceiling
Design elements Continuous wall lighting, even around corners T5 or T5HO lamping Semi-specular reflector option boosts light down wall Easy installation onto wall-mounting rail System connectors allow continuous slot Contractor-friendly access to lamp and ballast compartment for maintenance 6" by 6" profile for restricted plenum depths Cradle to Cradle Silver CertifiedCM
SILV ER
No visible lamps
2100 lamp and ballast access
Complete fixture
Lamp chamber opened
Ballast cover opened
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Light with
Direct Lamps
Wall/Slot 85N The Wall/Slot 85N perimeter lighting system effectively lights the upper wall at the ceiling line. Measuring 9" wide by 10-1/2" deep, this luminaire is available for 1 or 2 lamps and up to three positions for mounting different lens and baffle options.
Baffle shown in F position
85N
3 5/8" (92) 10 1/2 Âą 3/4" (267 Âą 19)
9" (229mm)
Design elements Provides perimeter wall lighting from 9" slot 85N can be specified open or with a variety of baffles or lenses hidden in the lamp chamber (S), slightly regressed above the ceiling (R) or flush with the ceiling (F) System connectors allow continuous slot around a room, even around corners Easy installation with wall-mounting rail and hook-and-lock system Cradle to Cradle Silver CertifiedCM Van Wylen Library, Hope College Holland, MI, Architect - Shepley Bulfinch Richardson and Abbott, Photography - Nick Wheeler
SILV ER
Easy hook-and-lock system
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Light the walls
Wall/Slot 8400 The Wall/Slot 8400 is a perimeter luminaire that effectively lights the upper wall at the ceiling line. A smaller profile and shallower plenums than the 85N, the Wall/Slot 8400 provides a 6-1/2" wide by 6-5/8" deep luminaire for 1 lamp, with two positions for optional lenses or baffles.
8400 Baffle shown in S position 2 5/8" (67)
6 5/8" (168)
6 1/2" (165mm)
Design elements Provides continuous, direct wall lighting from a 6-1/2" slot Lamp chamber can be open with lamps visible from below Optional Soft Glow Lens (SGL) or Blade White (BW) baffle available at the lamp chamber opening (S-position) Soft Glow Lens can also be regressed above the ceiling (R-position) System connectors allow continuous slot around the room, even around corners Easy installation with wall-mounting rail and hook-and-lock system Cradle to Cradle Silver CertifiedCM
SILV ER
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Recessed Wall/Wash
Light with
Mod 44 WWD-4400 Litecontrol’s Mod 44 Recessed Wall/Wash is a 4" wide recessed luminaire designed for wall washing applications. The asymmetric reflector effectively washes the wall with light, while complementary optical elements control brightness to avoid glare.
4400 R-WWD 4 1/4" (108) 4 1/4" (108) 5 5/8" (143mm)
Design elements High performance luminaire for lighting chalkboards or whiteboards Ideal for retail applications that require vertical surface lighting on merchandise Narrow luminaire opening enables luminaire to blend into ceiling Continuous row mounting available T5 or T5HO lamping available for grid or plaster/drywall ceilings T8 lamping available for plaster/drywall ceilings
USGBC Headquarters
Cradle to Cradle Silver CertifiedCM SILV ER
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Light the walls
Conference Room Chicago, IL Charles Mayer Photography
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Light the walls
Products
Series
Wall/Slot 2000
2000 2000PR
Slot Height Lamping Features & Options Opening Above Ceiling Luminance Control Deflector minimizes socket shadows Lamps and luminaire hidden from view Parabolic reflector option boosts light down the wall 9"
10 1/2"
Wall mounting rail for easy installation System connectors allow for continuous slot around space Cradle to Cradle Silver CertifiedCM
Wall/Slot 2100
2100
Lamps hidden from view Easy access to lamp and ballast components Semi-specular reflector option boosts light down the wall 6"
6"
Wall mounting rail for easy installation System connectors allow for continuous slot around space Cradle to Cradle Silver CertifiedCM
Wall/Slot 85N
85N
Available in one- or two-lamp cross-sections Shielding can be mounted at the ceiling level or above 9"
10 1/2" Âą 3/4"
Adjustable wall-mounting hook and lock installation system System connectors allow for continuous slot around space Cradle to Cradle Silver CertifiedCM
Wall/Slot 8400
8400
Hidden lens or baffle option Regressed lens option System connectors available for corners 6 1/2"
6 5/8"
Hook and rail mounting system System connectors allow for continuous slot around space Cradle to Cradle Silver CertifiedCM
Mod 44 Recessed Wall/Wash
4400
Asymmetric reflector designed for wall wash applications Requires only 4" above the ceiling Narrow aperture to minimize visual clutter 4 1/4"
4 1/4"
Painted reflector controls the luminaire brightness Continuous row mounting available Cradle to Cradle Silver CertifiedCM
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Light the walls
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QuickFind
Value Tier
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85
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For four years in a row, Litecontrol's focus on sustainability and our continuous improvement processes earned us the coveted Cradle to Cradle Silver CertificationCM for all products manufactured in our factories.
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Applications Key
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Shape perception. Enhance visibility and comfort.
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Light the walls