Area-and fixture-based controls can each play a role in the same installation
By David Parrett
Efficiently designing lighting for a commercial space can be a challenge because in some situations it requires the ability to see into the future. A commercial space could start off as a coffee shop but the next tenant could be a dental office. Or, it could be an office space that is restructured over
time to create a larger conference room and additional cubicles. The most flexible control option for commercial spaces is fixture-based controls, but there are also benefits to area-based controls, and for most buildings a blend of the two will be the ideal networking solution.
The control option does not affect design and functionality alone; efficiency also has to be taken into consideration, especially for buildings that can benefit from or are required to adhere to utility energy efficiency programs. While area-based controls might seem like the most energy-efficient option, fixture-based controls can offer more options for reducing lighting use depending on how a commercial space is utilized.
Overall there are many factors to account for when planning networked lighting control. Instead of choosing one or the other, building designers and architects will be best served to plan space-by-space within a building and weigh the pros and cons of each option.
Typically, large open spaces that function as a common area and are heavily trafficked will benefit from area-based controls. These types of spaces can include store rooms, classrooms, conference rooms, ballrooms, lobbies, break rooms and community work spaces in offices. Area-based controls allow for all of the luminaires in these areas to be virtually controlled as one entity. There is no need for nuanced lighting in these spaces, so simply being able to turn all the fixtures on and off in the space is enough. Area-based controls do not mean that the lighting has to remain static throughout the day and dimmers or other lighting modifiers are still possible. Area-based controls can also be included in larger zones virtually, the intent being that daisy-chaining of multiple fixtures into a single area does not preclude that area from being included in broader zones. Whether using fixture-level control or area control, adapters can always be grouped together using software so they behave as one larger group.
The benefits of area-based controls are that they can be applied to most situations, configuration is simple and they are a good fit for retrofit projects. The area-based approach is good enough for most spaces, since it meets design needs at a reasonable cost, sharing one control adapter across many fixtures. This method also reduces complexity of design with fewer end nodes to find and configure. In the case of a retrofit, it offers the ability to swap out a switch and control an entire bank of lighting.
The drawbacks of area-based controls are potentially higher labor costs, sacrificing nuanced control and the lack of future adaptability. In a retrofit situation, installers may need to run control wires, which also adds labor cost to the equation. The area-based approach results in a loss of control for individual “spots” of light, and instead creates “pools” of light. If the layout of the space changes in the future, it’s much more difficult to reconfigure the lighting design.
While area-based controls make sense for large spaces with many luminaires, fixture-based controls can better serve small, private-use spaces within a building, such as individual offices. Fixture-based controls are also a good option for intricately designed spaces that incorporate specialty lighting features such as spotlighting capability.
Fixture-based control is accomplished when each luminaire is wired to a single fixture adapter. Network lighting controls allow for fixture-based controls to be included in larger zones virtually, but the luminaires maintain an ability to be controlled individually.
Executing fixture-based controls is a straightforward process for electricians. Fixture adapters are installed at each fixture, so control wires do not need to be installed between luminaires. But that does not mean that a fixture-based control system is more cost-effective than an area-based one. More adapters can increase costs and the configuration of the system takes more time and is more labor intensive. The long-term benefits of fixture-based controls can be appealing for commercial spaces that will be used in different ways over time.
As the building’s layout or needs change, the system can be easily updated. It’s not uncommon in a tenant situation to have to change offices, add cubicles or move walls. If you have control over every fixture, you can use software to change the zones very easily.
Visualize and Plan
When planning for network lighting controls, designers should start by considering the density of fixtures and the activity beneath them. Remember, one option is not better than the other. While an area-based approach may be better in an open-office plan, individual offices may do better with individual fixture control. Common spaces like lobbies and break rooms are always best when planned for area control, when you need to illuminate all or none. And while it is impossible to know what future tenants will require from a space, it is possible to plan for future flexibility.
The secret to successfully planning network controls is to visualize daily activity in the building. A mental walkthrough of the space can help determine what areas of the building will benefit from area-based or fixture-based controls. It can also help determine what luminaires should be grouped together for zones. Remember, whether a space is controlled by fixture or area, the luminaires in that space can also be designed for zone-based controls using software. There can be many layers of lighting controls within a building, but the building blocks are fixture and area controls and choosing the right blend can increase functionality and lessen cost burden. In a final design, most buildings will benefit from greater control with a fixture-level approach in individual office settings, and an area-based approach in the public settings.