Deciphering 2018 IECC—Light Reduction Controls

In the IECC standard, two techniques work together to reduce energy usage in most indoor commercial spaces: Interior Manual Lighting Controls (referring to manual control capabilities) and Light Reduction Controls (specifying that those manual controls must be capable of dimming and/or multi-level switching).

  • Areas enclosed by walls or floor-to-ceiling partitions must have at least one manual control
  • The required control must be located in the area it is serving, or be a remote switch that identifies the lights it serves and indicates their status
  • Manual controls must be readily accessible to occupants
  • The areas required to have these manual controls must be able to reduce the area lighting by 50% in a “reasonably uniform illumination pattern,” which is normally achieved by either dimming or multi-level switching

These manual control guidelines are also commonly referred to as “partial-OFF” capabilities.

Note that 2018 IECC has additional unique requirements for manual control and light reduction that apply exclusively to open office areas. See our blog on 2018 IECC Open Office Areas for more information.

Summary of 2015 and 2018 IECC Requirements
C405.2.2.2 Light Reduction Controls

For more information and tools for 2018 IECC, visit

Partial-OFF Manual Control with Leviton

Easy-to-use, fully IECC compliant manual controls are available with dimming and partial-OFF capabilities, giving you the flexibility to design a system that works best for your application and occupant needs.

Lumina™ RF Standalone Room Controls

This easy wireless retrofit solution provides multi-zone control with full range dimming and scene control. Add additional capabilities with wireless sensors to meet additional IECC requirements. Set up and configuration is completed with the Lumina RF Standalone App.

Intellect™ Intelligent Fixture Control System

Delivers a configurable luminaire level lighting control solution for individual fixture and circuit control. Program and modify the system as business needs change with the Intellect App.  

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