Understanding the impact of IECC updates on lighting controls
Energy conservation is an important aspect of building design in today’s society. The International Code Council (ICC) has developed standards to encourage energy conservation through efficient design and installation of building envelopes and mechanical, lighting, and power systems. These standards are compiled in the International Energy Conservation Code (IECC), which is revised periodically to stay up-to-date on current technology and practices.
The code is implemented at the state and/or local levels, so depending on where a project is located, the design could have to adhere to the 2015, 2012, or 2009 IECC-or even no code at all. Although the 2012 IECC is not the most recent edition, it increases energy efficiency noticeably from the previous years’ versions and has been adopted by nearly half of the states.
Interior lighting plays an impactful role in the electricity usage of commercial buildings, and the 2012 IECC recognizes this by including various major updates to lighting control systems for energy conservation. It is important for design and construction teams to be aware of and understand the updated requirements and solutions for achieving these standards.
Lighting control updates
One of the biggest changes with the 2012 IECC is that it requires automatic lighting controls to be used in all buildings, not just those larger than 5,000 sq ft. In addition, in all projects where more than 50% of the lighting is being modified, either the total wattage is increased or the number of required fixtures is increased to meet the current code. This is in an effort to prevent the need to rely on people to manually turn off the lights.
In previous codes, commissioning was not strongly enforced, so another important update mandates that all projects require commissioning, which ensures that the lighting controls are designed according to code and perform as intended. Engineers must submit an energy-compliance form (COMCheck) that documents the lighting-power density (watts per square foot) as well as the lighting controls that are required. Then, each project needs to be inspected upon completion of construction and signed off to ensure it meets the IECC commissioning regulation. These measures increase the likelihood that the code is properly implemented in both the design and construction processes, and energy efficiency is realized.
Options for complying with the updates
Fortunately, there are multiple options available to ensure lighting design meets code requirements.
- Occupancy/vacancy sensors are useful for small spaces; however, in larger spaces they can become a nuisance if the lights automatically shut off when others are present in the general vicinity. Proper coverage design is critical. The architecture/engineering team is wise to require the sensor manufacturer to provide coverage-map shop drawings to ensure proper design.
- Timer panels allow the lights to turn on and off automatically on a timed schedule. Though the upfront cost may be a little higher, it ultimately translates to energy savings and cost savings. It’s also important to note that automatic switches and controls need an override switch that turns the lights back on for a maximum of 2 hours, per the code. This is a good solution for larger buildings and institutions where occupancy sensors may not be cost-effective or appropriate in every area of the building.
- Daylighting helps lower energy usage by using natural ambient light to reduce the amount of artificial light required in a space. As part of the 2012 energy code updates, daylighting must be used in any space that has a window, and the daylighting zone extends 2 ft beyond the window edges and 15 ft into the space. However, it is not required in spaces with two or less lighting fixtures, such as a private office. There are two options when it comes to daylighting: automatic and manual.
Beyond the 2012 IECC
The 2015 IECC further demonstrates the importance of lighting controls by employing even stricter metrics to the 2012 updates, but many states and local jurisdictions have been slow to implement this version. Examples of updates include:
- If only 10%-instead of 50% in the 2012 code-of lighting fixtures are altered, then the entire space is required to meet the 2015 code.
- Automatic daylighting is required within the daylighting zone rather than having an option between automatic and manual.
-This article originally appeared in an RTM white paper. RTM Engineering Consultants is a CFE Media content partner.