Overview of the International Energy Conservation Code® (IECC®)

Internationally, code officials recognize the need for a modern, up-to-date energy conservation code addressing the design of energy-efficient building envelopes and installation of energy-efficient mechanical, lighting and power systems through requirements emphasizing performance. The International Energy Conservation Code is designed to meet these needs through model code regulations that will result in the optimal utilization of fossil fuel and nondepletable resources in all communities, large and small.

This code contains separate provisions for commercial buildings and for low-rise residential buildings (three stories or less in height above grade). Each set of provisions, IECC—Commercial Provisions and IECC—Residential Provisions, is separately applied to buildings within their respective scopes. Each set of provisions is to be treated separately. Each contains a Scope and Administration chapter, a Definitions chapter, a General Requirements chapter, a chapter containing energy efficiency requirements and existing building provisions applicable to buildings within its scope.

This comprehensive energy conservation code establishes minimum regulations for energy-efficient buildings using prescriptive and performance-related provisions. It is founded on broad-based principles that make possible the use of new materials and new energy-efficient designs. This IECC is fully compatible with the Family of International Codes.

Benefits of the IECC:International Energy Conservation Code Book Cover

  • The 2018 IECC contains a reorganized Commercial Mechanical Section C403 where all provisions a type of equipment or system are in one place; for example all Economizer requirements are found in Section 403.5.
  • The 2018 IECC requires controls on hotel guest room HVAC systems to automatically adjust when the room is unoccupied.
  • The 2018 IECC contains improved provisions for lighting controls including occupant sensor controls; daylight response controls and time based switch controls.
  • The 2018 IECC includes an appendix chapter which, when included in a jurisdiction’s adoption, requires commercial buildings to set aside roof space for future installations of solar collectors; and the connections and wiring to allow them to be integrated in the buildings systems.
  • The IECC is fully coordinated with the family of I-Codes to ensure that efficiency measures are selected and installed in a manner that does not compromise safety.
  • Provisions of the IECC encourage the use of new and smarter technological advances.
  • The IECC references nationally developed consensus standards.

Today's IECC is known for:

  • Conservation – It has a proven track record addressing the design of energy-efficient building envelopes and installation of energy-efficient systems.
  • Ease of Use – The IECC uses the same easy-to-use format provided in all I-Codes.
  • Embrace of New Technology – The IECC and its predecessors have a tradition of innovation while protecting the health and safety of the public.
  • Correlation – The IECC is specifically correlated to work with ICC's family of codes.
  • Open and Honest Code Development Process – The IECC is revised on a three year cycle through ICC's highly-respected consensus code development process that draws upon the expertise of hundreds of plumbing, building and safety experts from across North America.

 Code Development

Current Version: 2018 IECC

  • Purchase the newest edition of the code and references.

Upcoming Version: 2021 IECC Development

The International Energy Conservation Code provisions provide many benefits, among which is the model code development process that offers an international forum for energy professionals to discuss performance and prescriptive code requirements. This forum provides an excellent arena to debate proposed revisions. This model code also encourages international consistency in the application of provisions.

Get Involved

Adoptions of the IECC

The International Energy Conservation Code is in use or adopted in 47 states, the District of Columbia, the U.S. Virgin Islands, New York City and Puerto Rico.

As a model code, the IECC is intended to be adopted in accordance with the laws and procedures of a governmental jurisdiction. When adopting a model code like the IECC, some jurisdictions amend the code in the process to reflect local practices and laws.


Support references for the IECC

ICC publishes a wide range of support products and materials to help users and enforcers of the IECC to improve their knowledge and understanding of the code. Several key publications are provided below, or get the full list from the ICC Store.


Certification of Personnel

ICC offers certification programs for inspectors and examiners to the International Energy Conservation Code. Current certification programs specifically designed for the IECC include:

Residential Energy Inspector, Commercial Energy Inspector, Commercial Energy Inspector with ASHRAE 90.1, Commercial Energy Plans Examiner, Commercial Energy Plans Examiner with ASHRAE 90.1, and Green Building—Residential Examiner.

ICC-ES Evaluation Reports

ICC Evaluation Service (ICC-ES) is the United States' leader in evaluating building products for compliance with code. A nonprofit, public benefit corporation, ICC-ES does technical evaluations of building products, components, methods, and materials.



In addition, ICC-ES is recognized by the U.S. Environmental Protection Agency (EPA) to certify products in the following areas:

  • Certification of roofing products under the EPA ENERGY STAR® program
  • Certification of products under the EPA Seal and Insulate with ENERGY STAR® program

Technical Opinions

Staff Code Opinions and Committee Interpretations are intended to provide technical support and clarification of code text for adopting jurisdictions, design professionals, and members of the construction industry. Technical Opinions on codes and standards are an exclusive benefit of ICC Membership.


Training and Education for the IECC

ICC provides a full suite of training courses geared specifically for the IECC. ICC instructors provide hands-on, practical problem-solving training and are available to teach on-site single or multiday courses. For more information, visit the ICC Learning Center.

Select topics include:

  • 2015 IECC Essentials
  • 2012 IECC Update
  • 2012 IECC Significant Changes
  • 2012 IECC Fundamentals
  • 2012 IECC Performing Residential Energy Plan Reviews
  • 2012 IECC Performing Residential Energy Inspections
Get Involved

Get Involved

ICC operates a number of committees and councils related to the development and maintenance of codes and standards. There are several that relate specifically to the IECC.

  • Sustainability, Energy and High Performance Building Code Action Committee
  • Commercial Energy Code Committee
  • Residential Energy Code Committee
  • IgCC Energy and Water Code Committee
  • Energy Conservation, Existing Building, Green, Property Maintenance, Zoning Code Interpretation Committee