Choosing a Design Philosophy for the Lighting System
If there is any silver lining to the continued rising cost of energy, it may be that the ROI for lighting upgrades is improving. Better returns make it easier now to get the CFO on board with budget requests. However, the flip side is that the rising cost of energy also means that budgets are much tighter, and projects — even those with a good ROI — may be scrutinized more than ever before, so facility executives need to be certain to do their due diligence. Will the lighting specified meet quality, performance and cost criteria? How can you be sure? What if the system does not satisfy expectations? Who will be responsible if it does not? How will it be fixed?
When sending a lighting system for bid, facility executives soon learn that different suppliers have different recommendations using different products or methods to achieve the same goals. Sometimes, the suppliers know little about the process that created the initial specification. They are looking at the components listed hoping to make a sale. The availability of several different solutions may be beneficial. It could also be a big problem.
There are ways to produce and manage specifications to help minimize problems like these. Creating good specifications and a successful lighting installation involves a minimum of five phases of active involvement that facility executives should be aware of:
- Design: information gathering and developing the lighting solutions.
- Creating good specification documents.
- Bid pricing: product review and approval.
- Implementation: managing the design specifications during construction.
- Commissioning: final review, punch list, aiming of adjustable lights, programming and verification of control systems.
All five parts are needed to achieve successful results.
To begin with, it is important to understand that there are two ways to begin the specification process. Both may yield very different results. The first is the “engineered” lighting approach and the second is the “designed” lighting approach.
In simple terms, engineered lighting specifications are created when the lighting solutions are based primarily on first selecting products to replace old ones or when new products are needed for a new installation. Then, footcandle calculations are provided and specifications are written based on this very basic information.
A lighting engineer, contractor or product sales person may provide the specification based on the facility executive’s desired solution. The criteria may be simple, such as reduce energy costs or make a space brighter. Engineered lighting specifications do not involve a comprehensive design process; therefore they may not address key, important issues and are more prone to value engineering. They are the standard, quick-fix to lighting problems.
Designed lighting specifications are created with a design process to address a lighting problem. A design process begins with the designer or specifier, facility executive and even users getting together to ask and answer questions. Then, lighting goals and objectives are established. The goals and objectives define the lighting solutions and establish the basis for the lighting specifications.
The designer or specifier should address the numerous issues described in the new Lighting Design Guide found in the Illuminating Engineering Society of North America Handbook, Chapter 10, Quality of the Visual Environment. Addressing the points made in this chapter leads facility executives through all of the important considerations required for good lighting solutions. Unfortunately, many lighting specifiers are not aware of this resource or do not understand the importance of following it. It raises the minimum standard of care required by designers in providing lighting specifications to projects where the quality of the visual environment is important to good visibility. In the past, the minimum standard of care was simply meeting a footcandle criteria; the new standards have changed that. Lighting quality is essential to the success of the lighting system well beyond energy effectiveness.
In addition, a good design process will reveal that there may be many more issues important to lighting solutions than just lighting fixtures and lamps. These can include wall color, finish reflectance values, integration of electric lighting with natural light, lighting control systems, architectural integration, initial cost and long term operation cost comparisons and user preferences.