The office of tomorrow is an energy-efficient space designed for employee health and productivity, and today’s office is looking more like its future self every day. Lighting plays a key role. As an electrical contractor, if you remake your office to fit the needs of tomorrow, you can be an adviser that comes from a place of personal experience.
Tish Kruse, MRC, LEED AP, director of workplace strategy for IA Interior Architects, works out of the firm’s Chicago office. She finds space planning and lighting design go hand-in-hand.
“Saving money through efficient building operation and an efficient, stimulating workspace for employees each affect the bottom line,” she said.
Skillfully employing natural and artificial lighting can promote employee happiness and productivity.
“Light makes a difference,” Kruse said. “Employees want good light. Daylight-harvesting systems attempt to do this when you have ample windows, but the trick is blending natural with artificial light.”
Shades and window films are also often needed to help mitigate glare and heat issues.
“When an office doesn’t have many windows, simulating the wavelengths of natural light through the careful selection and placement of lamps and fixtures is especially important,” Kruse said. “The addition of skylights can help, too.”
Lighting the new open office landscape
Though it may sound counterintuitive, it is possible to overlight a space as you drive efficiency. Ann Marie Krol, NCIDQ, LEED AP ID+C, is a senior associate for IA Interior Architects. Her firm addresses overlighting in the project design phase.
“We work with the manufacturer or lighting designer, sometimes the electrical contractor [EC], as we determine the watts-per-square-foot goal and figure out how to how meet it,” she said. “For us, the lighting is based on employee tasks and should be tuned accordingly. To better light the work desk surface, low-draw LED [light-emitting diode] task lighting is starting to play a role.”
Krol explained the trend in today’s open office design is to illuminate more evenly throughout the space, not just where someone sits. Often fewer ceiling fixtures are used or needed. Closed office spaces may still have direct overhead lighting, but now it is user-controllable.
[SB]“Lighting controls are becoming standard components,” Krol said. “The ability to dial up or dial down lighting density gives us the precision to avoid over-lighting.”
She added that design work sessions address what will work, what might not, and at what cost, so everyone is on the same page.
“The electrical contractor is very helpful as we look at lighting- control systems and their capabilities, dimming protocols, and ability to work with other systems,” Krol said. “Everyone comes away learning something from another trade. These design meetings also allow the EC to determine what runs might be needed, what could be wireless, and so forth. Wireless is certainly growing in popularity.”
Avoiding the panacea mindset
Our connection to the outdoors is strong. We are drawn to it because it benefits our mood, concentration and other factors. In new office design, IA Interior Architects strongly advocates for better use of the light windows can provide. Daylight harvesting is one technique to efficiently take advantage of natural light while better managing artificial lighting costs. However, it requires thought and precision.
“You need to understand how the lighting will feel when the harvesting is occurring,” Krol said. “Discover that sweet spot between daylight and artificial lighting to achieve even light levels. Make step-dimming imperceptible to the worker. For example, on brightly lit days with an open work station and lighting fixtures running perpendicular from the exterior wall, adjust your dimming down to between 0 to 10 percent. It will help even out the light as it extends into the space. You will need a sensitive ballast.
“We’ve had clients run their lighting at 80 percent or less without affecting worker performance. We will also use light [color] wall finishes to effectively bounce light off the ceiling and walls to further efficiency. Some clients have seen a lighting controls cost return in as low as two years.”
Karl F. Johnson is a project manager for the California Institute for Energy and Environment (CIEE) at the University of California, Berkeley. The CIEE works to accelerate energy efficiency and environmental solutions in line with the goals of the California Energy Commission. Johnson is with the buildings program, which supports a strategic lighting plan to help meet Title 24 state mandates of net-zero for new residential construction by 2020 and commercial buildings by 2030. Within those mandates are retrofit goals, as well. State universities are committed to be carbon-neutral by 2025.
“We both conduct R&D [research and development] and demonstrate new technologies working with the manufacturers,” Johnson said.
He has found that a network-enabled lighting system can help meet demanding efficiency goals.
“I feel network controls are essential to meeting your daylight-harvesting objectives,” Johnson said. “They offer the biggest benefit to getting daylight harvesting right, beyond initial commissioning after pre-installation and sensor placement. Such controls have a metering system, featuring reading sensors for daylighting, occupancy and so forth. You can easily see if you are falling short, then fine-tune settings often through a laptop.”
Through CIEE demo and testing, Johnson feels confident quality office lighting can be achieved at 0.2–0.3 watts per square foot when using the latest LED dimming fixtures, networked controls for tuning, occupancy and daylighting, and LED task lighting. Such results were achieved in a University of California, Santa Barbara campus demo conducted under the now former State Partnership for Energy Efficient Demonstrations (SPEED) program.
“Every time we set the lighting in a demo space, we found we could drive lighting levels lower than we thought possible without affecting worker performance,” Johnson said. “The real commissioning comes from workers in the space who provide feedback. Having that network control and the ability to reset the control is a game changer.”
IA Interior Architects revisits its clients 30 days after an initial design installation, then again at 60 days, commissioning as needed by factoring in employee response.
NECA/LA and IBEW 11 helped to develop the advanced lighting controls training and certification for the California Advanced Lighting Controls Training Program. (For more on CALCTP, see “Narrowing the Gap,” Electrical Contractor, September 2015.) The program works to increase the use of lighting controls in commercial buildings and industrial facilities. Johnson acknowledged networked controls can be challenging when system components come from multiple companies—one providing the ballasts, another the sensors, and yet another the fixtures. One solution is integrated systems offered by a handful of companies, but they will come at a higher price, he said.
Both Krol and Johnson are enthusiastic about LED lighting, though Krol said that maintaining successful color rendering still needs work. When it comes to efficiency gains, Johnson is all in with LEDs, seeing them as the primary office space lighting source.
“In California, we must meet ambitiously set energy- reduction goals,” Johnson said. “Why swap out lighting every couple of years with a light source that only gradually ramps up its efficiency? Turn to one [LED] that is offering the efficiency you’ll need tomorrow, today. It helps that LED-retrofit kits are certainly much better now.”
“I’m in the blended lighting camp,” Krol said. “I like using different lighting, not just one type. I want lighting that provides true, maintainable color temperature. You don’t always get that with LED, which can go blue or pink. Sometimes the owner will be resistant to changing out fixtures, so you have to be creative with what you’re given to meet efficiency goals.”
Going forward, office design will be all about efficiency both in space and lighting. Learn and practice all you can because the EC will be front and center during this transformation.