In November 2014, ASHRAE published ANSI/ASHRAE/USGBC/IES Standard 189.1, Standard for the Design of High-Performance, Green Buildings Except Low-Rise Residential Buildings.

The standard, which updates the previous 2011 version, covers site sustainability, water use, energy, indoor environmental quality, and the building’s impact on the atmosphere, materials and resources.

The standard provides states and other jurisdictions a green building standard in mandatory code language. These jurisdictions can adopt Standard 189.1 in whole or in part. The U.S. Green Building Council (USGBC), creators of LEED, supported the development of 189.1 because LEED is a voluntary green building rating system, not intended to be a code. Another green building model code is the International Green Construction Code (IgCC), published by the International Code Council (ICC), which recognizes 189.1 as an alternative compliance standard.

In August 2014, ARCHITECTURAL RECORD reported that the USGBC, ASHRAE, AIA, IES and ICC partnered to harmonize 189.1, IgCC and the LEED rating system. Under this agreement, 189.1 will provide the baseline requirements aligned with LEED prerequisites and the IgCC. The IgCC will provide as an alternate set of prerequisites for LEED. ASHRAE, USGBC and IES will sponsor IgCC, and the ICC and AIA will sponsor 189.1. Integrated development will be managed by a steering committee.

The result will be a streamlined and effective set of regulatory options for jurisdictions across the United States, aligned with LEED. Regulators get the right tool for the job, adopting code-ready language instead of trying to codify LEED. Designers ideally will get less confusion.

The lighting sections of ASHRAE/IES 189.1-2014 primarily cover light pollution, energy efficiency, daylighting and occupant lighting control. Each major section is divided into three main areas: Mandatory Requirements plus a Prescriptive Option and a Performance Option. As indicated by its name, Mandatory Requirements are mandatory. The Prescriptive Option entails completing the Mandatory Requirements plus a series of prescriptive requirements. The Performance Option involves simulation and related calculations.

This special report by the Lighting Controls Association summarizes the lighting and control requirements. Note that for each feature described, exceptions may apply. Consult ASHRAE/IES 189.1-2014 and the authority having jurisdiction for specific requirements and interpretation relevant to your project.

Lighting and controls

In regards to energy-using building systems, ASHRAE/IES 189.1-2014 references the ASHRAE/IES 90.1-2013 energy standard as a baseline. Lighting and controls must comply with Section 9 of 90.1-2013 with some modifications and additions.

Energy Efficiency (Section 7)

Mandatory Requirements:

1. For lighting systems constituting a connected load greater than 50 kVA, energy consumption must be measured using a device with remote communication capability. At a minimum, data must be recorded at least hourly and provided at least daily. Data must be transmitted to a data acquisition system that stores the data for a minimum of three years. The system must be capable of generating user reports at least monthly and containing hourly, daily, monthly and annual energy consumption. Section 7.3.3.

Prescriptive Option requirements:

1. Interior and exterior lighting power allowances lower than 90.1-2013 are in effect. This is accomplished by referencing a factor in a table. For example, using the Building Area Method, the lighting power allowance for office building areas is 0.82W/sq.ft. Standard 189.1-2014 presents a multiplier of 0.95, so if using the Building Area Method, the designer would have an interior lighting power allowance of 0.95 x 0.82. Section 7.4.6.1.

2. Satisfaction of ENERGY STAR performance criteria is required for installed lighting that includes integral LED lamps. If the Alternate Renewables Approach is taken (Section 7.4.1.1.2), satisfying ENERGY STAR criteria is also required for lamps and both commercial and residential luminaire types covered by the labeling program. Section 7.4.7.3.

3. Hotels and motels with more than 50 guest rooms must install automatic controls for the lighting, switched outlets, TV and HVAC equipment serving each guest room. Within 30 minutes of the room becoming vacant, the control device must automatically turn OFF power to lighting and switched outlets. Captive keycard systems are not recognized for compliance. Section 7.4.3.9.1.

4. Lighting in commercial and industrial storage stack areas must be controlled by an occupancy sensor. The sensor must reduce lighting power by at least 50% within 20 minutes of the stack area becoming unoccupied. Section 7.4.6.2.

5. Continuously illuminated security and emergency lighting is limited to 0.1W/sq.ft. Additional security and emergency lighting can be added as long as it is controlled by an automatic control that turns it OFF when it is not needed. Section 7.4.6.3.

6. Sign lighting that operates more than one hour per day during daylight hours must be operated with controls that automatically reduce lighting power by at least 65% for one hour after sunset to one hour before sunrise. A notable exception is metal halide, high-pressure sodium, induction, cold cathode and neon sign lighting that automatically reduces lighting power by 30% during the same hours. Section 7.4.6.4.

7. All other sign lighting must feature controls that automatically turn the lighting OFF during daylight hours. The controls must automatically reduce the lighting power by at least 30% for period from midnight (or within an hour of the end of business operations, whichever is later) to 6:00 AM (or business opening, whichever is earlier). Section 7.4.6.4.

8. Exterior lighting serving uncovered parking areas must be controlled by a photosensor that automatically turns OFF the luminaire during daylight hours. The lighting must also feature an astronomical time switch that turns the luminaires OFF on a schedule. Section 7.4.6.5.

9. An exterior luminaire serving an uncovered parking area, if larger than 50 rated input watts and mounted 24 ft. or less above the ground, must be automatically reduced based on occupancy. Specifically, lighting power must be reduced by at least 40% when no activity has been detected in the controlled area after 15 minutes or less. No more than 1500W of lighting power can be controlled by a single controller. Section 7.4.6.5.

Note that the above or any other controls required in 189.1-2014 that coincide with stretch control options in 90.1-2013’s Table 9.6.3 cannot be applied to earn bonus power credits.

Site sustainability (Section 5)

Mandatory Requirements:

1. Exterior luminaires must have controlled backlight and uplight emissions plus glare control so as to minimize “light pollution.” Exterior luminaires must meet BUG (backlight, uplight, glare) ratings, referenced in IES TM-15, Addendum A. Section 5.3.6.

2. Exterior luminaire uplight emission (percentage of light emission above 90 degrees) is restricted based on lighting zone, in turn based on population density (see the definitions). Section 5.3.6.

Indoor Environmental Quality (Section 8)

Mandatory Requirements:

1. Lighting in at least 90% of enclosed office spaces (<250 sq.ft. of floor area) must provide multilevel lighting control or bilevel control with separate task lighting. Section 8.3.5.1.

2. Multilevel lighting control is also required in multioccupant spaces, including conference rooms, meeting rooms, multipurpose rooms, classroom (or other training or lecture rooms), ballrooms, cafeterias and gymnasiums. Each control device must be labeled with its light settings. Section 8.3.5.2.

3. Gymnasium, auditorium, ballroom and cafeteria lighting must be zoned as at least two independently controlled groups of luminaires. Section 8.3.5.2.

Prescriptive Option:

1. Luminaires installed 3 ft horizontally of any permanently installed presentation surface (such as a whiteboard, chalkboard or projection screen) must be controlled separately from other general lighting in the space. Each control device must be labeled with its light settings. Section 8.4.3.

Performance Option:

1. Lighting must be provided for each permanently installed presentation system. The lighting must be controllable by the occupant or occupants. Each control device must be labeled with its light settings. The light settings at a minimum should include those below, depending on the type of presentation system.

2. Permanently installed whiteboards: The lighting and controls must be able to light the whiteboard with a vertical light level of an average of 300 lux (about 28 footcandles, rounding up) or higher. The average-to-minimum light level ratio across the whiteboard’s full area must be 3:1 or lower.

3. Permanently installed screens for front-screen projection units: The lighting and controls must be able to light the screen to a vertical light level of 50 lux (about 5 footcandles, rounding up) or lower. Maximum-to-average light level ratio across the full screen must be 2:1 or lower. Compliance is not met by turning OFF all luminaires in the space.

4. Permanently installed screens for rear-projection units: The lighting and controls must be able to light the screen to a vertical light level of 150 lux (about 14 footcandles, rounding up). Maximum-to-average light level ratio across the full screen must be 2:1 or lower. Compliance is not met by turning OFF all the luminaires in the space.