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


The standard allows states and other jurisdictions to regulate green building design using mandatory code language rather than LEED, which is a rating system for green buildings, not a code. One 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 summer 2014, the governing organizations partnered to harmonize 189.1, the IgCC and the LEED rating system. Standard 189.1 will provide the baseline requirements aligned with LEED prerequisites and the IgCC. The IgCC will provide an alternate set of LEED prerequisites.


The lighting sections of 189.1 2014 focus on energy efficiency, light pollution, daylighting and occupant lighting control. The standard references the ANSI/ASHRAE/IES 90.1 2013 energy standard as the baseline of what must be done and then makes modifications and additions. For each major section, the requirements are divided into three parts: mandatory (prerequisites), prescriptive option (mandatory plus a set of prescriptive requirements, relatively simple) and performance option (simulation, relatively complex). Below is a brief description of the lighting requirements, minus daylighting.


Energy efficiency (Section 7) 


The mandatory requirements call for energy consumption measurement and reporting. Energy consumption for lighting systems representing a connected load greater than 50 kilovolt-amperes must be separately measured using a device that offers remote communication with a data acquisition system. The system must store the information and generate user reports.


In the prescriptive option, interior and exterior lighting power allowances lower than 90.1 2013 are in effect. This is done by referencing a factor in a table. For example, using the building area method, the lighting power allowance for office building areas is 0.82 watts per square foot (W/sq.ft). Standard 189.1 2014 presents a multiplier of 0.95, so the designer would have an interior lighting power allowance of 0.95 × 0.82.


Hotels and motels with more than 50 guestrooms must install automatic lighting controls for each room’s lighting; switched outlets; TV; and heating, ventilating and air conditioning (HVAC). Power to the lighting and switched outlets must be automatically turned off within 30 minutes of the room becoming vacant. Captive keycard systems are not recognized for compliance.


Lighting in commercial and industrial storage stack areas must be controlled by an occupancy sensor that reduces lighting power by at least 50 percent within 20 minutes of vacancy. Continuously illuminated security and emergency lighting is limited to 0.1W/sq.ft. More can be added if it is connected to a control that automatically turns it off when not needed.


Sign lighting must be operated by controls that automatically reduce lighting power, with the level of reduction dependent on whether it operates during daylight hours and the lamp type.


A photosensor and astronomical time switch must control exterior lighting serving uncovered parking areas. If larger than 50W and mounted 24 feet or less above the ground, lighting power must be automatically reduced by at least 40 percent after the controlled area becomes vacant for 15 minutes. No more than 1,500W of lighting power can be controlled by a single controller. 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.


Installed integrated light-emitting diode (LED) lamps must meet Energy Star performance criteria. If the Alternate Renewables Approach is taken (Section 7.4.1.1.2), it is also required for any installed lamps and both commercial and residential luminaire types covered by the labeling program.


Site sustainability (Section 5)


This section requires exterior luminaires to have controlled backlight and uplight emissions as well as glare control to minimize light pollution. Exterior luminaires must meet backlight, uplight, glare (BUG) ratings, referenced in IES TM-15, Addendum A. Uplight (percentage of light emission above 90 degrees) is restricted based on lighting zone.


Indoor environmental 
quality (Section 8) 


This section requires lighting in at least 90 percent of enclosed office spaces (if less than 250 square feet of floor area) to provide multilevel lighting control or bilevel control with separate task lighting. Multilevel control is required in listed multioccupant spaces (e.g., classrooms). Gymnasium, auditorium, ballroom and cafeteria lighting must be zoned as at least two independently controlled groups of luminaires.


The prescriptive option includes a requirement for presentation lighting to be controlled separately. It requires the lighting and controls to satisfy certain illumination criteria, depending on whether the permanently installed presentation system is a whiteboard or rear- or front-projection screen.