State and local governments write into law building codes that are regulations for buildings and other structures. The main objective of these codes and standards is to protect the safety, health, and general welfare of the public as it relates to the occupancy and construction of buildings and structures. It’s important to understand that these codes are written at the state (and sometimes local) level. The United States does not have a national code.
These codes relate to many aspects of building construction and maintenance. These include occupancy safety, structural safety, electrical, plumbing, and energy use. A structure’s lighting system has codes and standards that not only relate to public safety but also its energy consumption.
Regulation of the designed energy efficiency of nonresidential buildings is the aim of building energy codes. A wide range of lighting controls is required by current codes and standards to ensure that general lighting is turned off or decreased when it is not needed.
Energy codes are among other commercial building codes which include fire, electrical, structural, and plumbing. They are not the same as codes for equipment or appliances. They are related to the building itself. However, there is an overlap with lighting in some cases.
The most common codes adopted by state and local governments are as follows:
The ASHRAE/IES 90.1, Energy Standard for Buildings was created as a standard energy code that jurisdictions can implement partially or entirely. It is updated every three years. The most recent version is ASHRAE/IES 90.1-2019.
The United States Department of Energy decreed ASHRAE/IES 90.1 as the national energy reference standard. It requires all states to adopt a code at least as strict.
The IECC is a standard residential and commercial building energy code. It is written and revised by the International Codes Council (ICC). Like the ASHRAE/IES 90.1, it is revised every three years. The most recent version is ICC IECC 2021.
The IECC mentions ASHRAE/IES 90.1 as an alternate model. This offers an added choice for building designers.
More information about the IECC can be found here: https://www.iccsafe.org
ASHRAE/IES 90.1-2019 and IECC 2021 require strict and mandatory conditions for lighting systems. A wide range of lighting controls is necessary. These controls have to be functionally tested and documented. The designed power should not go beyond the mandatory maximums. Documentation that is related to the lighting and control system must be given to the owner.
Each code describes requirements for lighting. They are defined as the overall lighting power permitted, alongside prescriptive requirements involving lighting controls and operation. Most jurisdictions demand that a project design complies with IECC or ASHRAE 90.1.
All the codes require some type of automatic shut-off for most interior lighting. This is accomplished with occupancy sensors or with timer controls. ASHRAE 90.1 demands that manual controls are available to building occupants for all of its interior lighting. For most spaces, all the codes require a “partial-on” function. This function limits the lighting power of the first stage to 50% or less of the connected lighting power. All codes require light-reduction controls that offer at least one control option with significantly decreased lighting power.
Lighting power-reduction controls can be achieved by the following:
The codes require that the lighting is fairly uniform when lighting power controls are active. Dimming all the fixtures together makes it easy to maintain uniformity. The dimming ability of LED lights makes them an effective solution for lighting power controls.
Automatic daylight-responsive controls are required by all the codes in spaces where daylighting is available. This can be from areas that have windows or skylights. ASHRAE 90.1 requires at least four illumination levels:
Exterior lighting must be turned off by photocells or automatic timers during daylight hours. ASHRAE 90.1 and IECC require that ornamental hardscape and façade lighting is automatically turned off at particular times. This generally applies to opening and closing times, and also with dusk and dawn controls. Any remaining outdoor lighting must be controlled so that there is a reduction in the total lighting power in response to motion sensors. ASHRAE 90.1 and IECC mandate a 30% reduction.
Commercial building energy codes incentivize the installation of a robust control system. This is especially the case regarding lighting and controls. The most common idea is that lighting must be turned off or decreased when it is not needed. This system can be an enhanced efficiency option or a method to achieve a higher interior lighting power allowance. Occupancy sensors are required in a wide range of areas. Separate controls are required for daylight areas. In some cases, this includes secondary areas.
Finally, it’s important to understand that these codes and standards are always being revised and updated. Always make sure that you are up to date with the latest developments and are able to provide the required testing and documentation information as needed.
