There was a lot of buzz around the residential provisions in the 2015 International Energy Conservation Code (IECC) last year but not enough around the commercial provisions. So what are some major changes for commercial buildings in the 2015 IECC? Here is a summary:

Increased Commissioning!

One of the major changes to the 2015 IECC that would help improve code compliance is the scope of increased commissioning. In the new code, commissioning is applied to HVAC, all lighting systems including occupancy sensors and daylighting controls, building service water heating systems, and the entire building envelop using approved third parties for verification. The commissioning requirements also include a detailed list of items in order to complete commissioning.

HVAC, Water Heating, and Lighting Get Major Upgrades

In addition to the mandatory commissioning discussed above,

• HVAC upgrades include new equipment requirements on minimum efficiency air-conditioners and condensing units serving computer rooms, improved energy recovery ventilation systems, and specifications for motorized dampers to better control outdoor air intakes, exhaust openings, stairway and shaft vents. The overall equipment performance requirements of the 2015 code result in bigger returns in energy efficiency through improved specifications of equipment efficiencies. Demand Controlled Ventilation (DCV) was also added as a mandatory requirement. The new code requires DCV to be provided for spaces larger than 500 ft² and with an average occupant load of 25 people/1000 ft² of floor, where the HVAC system has either an air-side economizer, automatic modulating control of outdoor air damper, or a design outdoor airflow higher than 3,000 cfm.
• The new water heating section provides improved requirements for electric, oil storage, and pool- water heaters. The minimum thickness for water heating pipe insulation is also greater than what is required in the 2012 IECC.
• The lighting systems also received an energy efficiency boost. The new lighting control section mandates occupant sensor controls for certain types of spaces and offers additional energy efficiency options. With the exception of warehouses, a list of space types in Section 405.2.1 are now required to have an occupancy sensor. The sensor in those spaces must be turned on manually or turned on automatically to a maximum-50% of lighting power. The sensor must turn off lights within 30 minutes of the space being vacated. Additional control requirements include time-switch controls for spaces (where occupancy sensor requirement are not applied), manual controls, daylight-responsive controls, and controls for specific applications such as retail display lighting. For exterior lighting control, all lighting, except for building façade and landscape lighting, must be turned off both in response to daylight and after the normal business hours.

Stay tuned for What’s New in the 2015 IECC Commercial Provisions? – Part II in the next issue of The Decoder. For more details on the major changes in the 2015 IECC, please see this resource by Britt/Makela Group.