National Electrical Installation Standards

Standards as High as Your Own

Friday, September 29, 2023


Hi CQD, thanks for all the great information. I own a small electrical contracting company that primarily does residential wiring. One of my customers also owns some commercial office buildings and has asked me to wire some of the spaces being remodeled. I met with electrical inspector regarding permitting and plan review, and they informed me that there are energy conservation requirements that must be met. I could not find anything in the NEC regarding energy conservation, other than the in Section 220.42(B) regarding load calculations. Where can I find the energy conservation rules for electrical systems? Thanks in advance, George M


Hello George, glad to hear you enjoy the CQD. Energy conservation falls outside of the purpose of the NEC® established in Section 90.2 as energy conservation is more of a design specification. The energy conservation rules used will depend on the local jurisdiction, as they are all a little different based on geographical needs. The most commonly used are the:

International Energy Conservation Code (IECC) published by the International Code Council (ICC) and ANSI/ASHRAE 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings, published by Illuminating Engineering Society (IEC). Your local AHJ will have more information on which energy code and which edition is used in your area.

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