Illinois to adopt 2018 IECC

Illinois is all set for a new energy code. In May 2019, the 2018 International Energy Conservation Code (IECC) will become law across the state.

Another change with the adoption is that state-funded buildings will follow the 2018 IECC with the American Society of Heating, Refrigerating and Air-Conditioning Engineers/Illuminating Engineering Society (ASHRAE/IES) 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings, as an alternative compliance path for a building owner and design team. Any plans submitted on or after the effective date are expected to follow the new energy code requirements.

The updated code will increase energy efficiency and lower energy operating costs for commercial buildings. Some of the changes are:

• occupancy sensor shut off time delay is lowered to 20 minutes;
• open plan office areas are now required to use occupancy sensor controls for lighting shut off;
• open plan office areas greater than 28 m² (300 sf) must limit the size of the occupancy sensor-controlled area to separate 56-m² (600-sf) zones and general lighting in the individual zones must reduce power by at least 80 percent when occupants are not detected for 20 minutes (when all individual lighting zones within the open plan office area no longer detect any occupants, the entire office area must shut off all lighting);
• new code provision allows the use of luminaire level lighting control (LLLC) technologies as an alternate lighting control compliance option, as long as the luminaires have embedded occupancy sensors, daylight sensing controls, dimming, and wireless zoning capabilities;
• an exception was added to allow a trade-off for daylighting controls (the exception requires an overall reduction of total building lighting power allowance equal to 40 percent of the allowed power for any daylight responsive zones receiving the exception); and
• interior and exterior lighting power tables are revised to reduce the lighting power allowance for many applications (this supports the shift to more energy-efficient lighting sources).

Illinois has made one amendment to the 2018 IECC in the electrical power and lighting systems section (C405.1). The amendment establishes light efficacy requirements for dwelling units that do not follow the residential code. In these cases, no less than 90 percent of the light in these units shall have lamps with efficacy of 65 lumens or more or light fixtures with efficacy of 55 lumens or more.