2021 IECC – A Code on a Mission – Toolkit

2021 IECC: A Code on a Mission – Campaign Toolkit

This Code on a Mission Toolkit supports communities and advocates with adoption of the 2021 IECC and it’s appendices and consideration of the 2021 IgCC. The toolkit includes the following resources:

Reasons for adopting the 2021 IECC

2021 IECCCommunities that regularly adopt the IECC save money for residents and business and improve community health and resilience. Some jurisdictions routinely augment the most recent model code with additional energy-saving code provisions or programs.

States are required to review their residential energy code and update their commercial energy code within two years of a positive determination from the Department of Energy that a new edition of the IECC saves energy.

Reasons to adopt the 2021 IECC fall into two categories: Energy Efficiency Improvements and New and updated provisions save energy, improve usability.

Energy Efficiency Improvements

On July 21, 2021, DOE Pacific Northwest Laboratory (PNNL) produced a final determination on the 2021 IECC representing a 9.4% site energy savings improvement and an 8.7% improvement in carbon emissions for residential buildings relative to the 2018 IECC, saving homeowners an average of $2,320 over the life of a typical mortgage.

DOE’s final determination can be found here.

The 2021 IECC represents an approximately 40% improvement in energy efficiency for residential and commercial buildings compared to the 2006 edition, meaning that residents in states and cities on older IECC editions would see far greater savings. The Department has also released data on energy, cost and GHG reductions each state and many cities could achieve by adopting the 2021 IECC, which are available here.

If all states updated to the 2021 IECC, nationally over 22,000 jobs would be created in the first year and over 632,000 jobs cumulatively over 30 years.

Each new edition of the energy code has provided for the cost-effective reduction of energy use. Implementation of the 2021 IECC is foundational to achieving energy savings and reductions on GHG emissions across building stock, both residential and commercial. According to the US Department of Energy, from 2010 to 2040, the model energy codes for residential and commercial buildings are projected to save:

  • $138 billion energy cost savings
  • 900 MMT of avoided CO2 emissions
  • 13.5 quads of primary energy

These savings equate to the annual emissions of:

  • 195 million passenger vehicles
  • 227 coal power plants
  • 108 million homes

For perspective, the primary energy consumption of the entire U.S. commercial and residential sectors in 2020 was estimated at 38 quads.

New and updated provisions save energy, improve usability

Key changes to the 2021 IECC improve efficiency by 9.4 percent and reduce greenhouse gases by 8.7 percent over the 2018 IECC; these changes include new provisions that increase efficiency and encourage greater flexibility in design and construction as well as changes to existing requirements that provide clarification and improve usability of the code.

View a summary of key changes here.

Additional Energy Efficient Packages

Three new additional energy efficient package options, as shown in the figure below, were added to the 2021 IECC. This addition brings the total number of energy efficiency compliance options to eleven. The purpose of this section is to provide flexibility to achieve the energy savings needed to meet the overall energy savings goal of the code. These additional requirements come into play during the design phase where the designer has chosen the Prescriptive Compliance option. Where a designer pursues compliance via meeting ANSI/ASHRAE/IESNA 90.1 or is using the Total Building Performance approach, then Section C406 does not need to be addressed.

  • More efficient HVAC performance
  • Reduced lighting power
  • Enhanced lighting controls
  • On-site supply of renewable energy
  • Dedicated outdoor air systems
  • High-efficiency service water heating
  • Enhanced envelope performance
  • Reduced air infiltration
  • Energy monitoring system
  • Fault detection and diagnostics
  • Efficient kitchen equipment

New Tropical Climate Zone Compliance Path

Tropical areas vary from the United States mainland in climate, construction techniques and energy prices. The new Tropical Climate Zone Compliance Path recognizes traditional tropical design characteristics encompassing shading, natural ventilation and the value of cool roofs. Mainland U.S. residential construction trends can minimize fenestration area, rely on dark roofing materials and overlook the value of external shading. Applied in tropical regions, these mainland construction trends result in overheated dwellings where natural ventilation is ineffective, yet the buildings lack the insulation and air sealing appropriate for any conditioned space. Additionally, tropical electrical prices make air conditioning infeasible for many households and, likewise, provide a substantial incentive for energy conservation.

Adoptable Appendix for Net Zero Energy Buildings

The 2021 IECC includes Zero Code appendices for both residential and commercial buildings.

The residential Zero Code appendix is based on the Energy Rating Index (ERI) path of the code, which requires more efficiency than is required in the base code and requires enough onsite or offsite renewable energy production to achieve an ERI score of zero. Renewable energy compliance may happen through a combination of onsite power production, energy generated through community renewable energy facilities, and renewable energy purchase contracts or leases.

The commercial Zero Code appendix is based on the Architecture 2030 ZERO Code. It requires a building to meet the minimum code requirements, plus enough on-site or off-site renewable energy to compensate for all the energy anticipated to be consumed by the building.

The Net Zero Energy provisions included in the 2021 IECC are not mandatory unless specifically referenced in the adopting ordinance. The provisions are included as appendices with the intention to provide options for jurisdictions with ambitious climate goals.

More information on Net Zero Energy – Building Operation Decarbonization can be found here.

Compliance and Enforcement

Adoption of the most recent model energy code is the first step to tapping into to cost-effective energy savings. Adoption should be followed by training and full implementation of the adopted code.

Although there is significant evidence of the value of energy code implementation, studies also show millions of dollars of untapped energy savings in states across the country. DOE has also observed, across 7 states studied, that training code officials on adopted codes can help reduce annual energy costs due to varying levels of code compliance by an average of about 45 percent.

Assessing the current construction practices, establishing compliance and enforcement goals, and accessing intake plan review inspection tools are the first steps to successful compliance and enforcement. Training requirements are equally important. The gap that exists between the efficiency levels required in codes and the efficiency levels achieved in the field is influenced by the extent of code official training on the energy code. Although about two-thirds of states require code official certifications, only seven states require training on energy code provisions.

More information on IECC Compliance and Enforcement can be found here.

Considerations for Adopting the 2021 IgCC

The International Green Construction Code (IgCC) is a collaborative effort of the Code Council, ASHRAE, the Illuminating Engineering Society and the U.S. Green Building Council to provide adoptable code language for communities that want to go beyond requirements contained in base codes. Although a stretch code currently, the IgCC sets the direction for the future of high performance building. The IgCC provides the design and construction industry with the single, most effective way to deliver integrated energy conservation, water efficiency, site and material sustainability, land use, and indoor environmental quality. It is currently adopted or in use in 13 states and DC and by the General Services Administration and the Department of Defense.

The 2021 edition of the IgCC offers essential sustainable construction building blocks on which future resilient initiatives can develop and expand. As jurisdictions continue to go beyond base codes to meet their robust climate and energy efficiency goals, the IgCC will be a critical part of the toolkit. The new edition provides:

  • Written-in, enforceable code language and overlays with I-Codes;
  • Extended scope to all areas of sustainable buildings and sites beyond energy conservation provisions of the IECC;
  • Ability to customize which requirements to adopt through a Jurisdictional Options table;
  • Appendix L, which aligns IgCC requirements with core elements of LEED versions 4.0 and 4.1;
  • Appendix M, which provides options for residential compliance with the National Green Building Standard (ICC 700).

Social Media Resources

Here are seven digital cards that you can post on social media that showcase the energy savings and efficiency of the 2021 International Energy Conservation Code®. Each card is available in 1200x630 and 1080x1080 dimensions for a total of 14 cards.


Partner Resources

Northeast Energy Efficiency Partnerships (NEEP)

Architecture 2030

American Council for an Energy Efficient Economy (ACEEE)

Polyisocyanurate Insulation Manufacturers Association (PIMA)

2021 IECC – A Code on a Mission – Adoptions

International Code Council

Leading the Way to Energy Efficiency News

Other Resilience and Climate Resources and Activities

ICC Performance Code Resources

Useful Websites for Reimagining the ICC Performance Code

Following is a brief list of websites that provide access to a range of information and experiences with performance-based building codes (regulation) and design approaches.

This is just a start – we know there is a lot of good information out there – including guidance within jurisdictions. If you have links that you think we should add, please let us know! While our aim is to point to freely available resources, we also provide a brief list of professional associations and others that have ‘for purchase’ documents.

Performance-Based Building Codes (Regulations)

The purpose of the Inter-jurisdictional Regulatory Collaboration Committee (IRCC) is to promote effective international collaboration concerning "best practice" building regulatory systems, in particular those that are functional, objective, or performance-based. This purpose necessitates interaction with bodies having compatible interests worldwide.

There are currently some 20 organizations from 17 countries represented in the IRCC.  From the "About Us" page on the IRCC website, you can find links to the websites of the participating entities.

In addition, under the "Documents" tab, you can find a number of summary reports, articles and other publications, largely pertaining to performance-based building regulatory systems. These documents are free to download.  These include the seminal 1998 document, Guidelines for the introduction of Performance Based Building Regulations, which served as a resource for many countries who embarked upon performance-based codes from the late 1990s onward, and the 2010 document, Performance-Based Building Regulatory Systems - Principles and Experiences, which provided context on the development and scope of performance-based building codes at the time.

Building Performance

The American Institute of Architects (AIA) offers a range of publications on building performance and sustainability and more. Their Commitment to the Architecture 2030 Challenge  aims to achieve better performing buildings that are carbon neutral by 2030. They aim for more use of performance-based design of buildings as well.

The mission of the National Institute of Building Sciences (NIBS) is to serve the public interest by advancing building science and technology to improve the built environment.  NIBS is active in construction issues, disaster resilience, and high-performing buildings, among other areas. With respect to high-performing buildings, NIBS and AIA collaborate on the development of the Building Research Information Knowledgebase (BRIK), an interactive portal to support incorporation of multidisciplinary research in the design, construction and operation of high-performance buildings.

Energy Performance

The U.S. Department of Energy  provides information on a number of energy performance and energy technology issues. Publications can be found based around specific focal areas, such as energy efficiency and renewables.

Fire Performance

The National Fire Protection Association (NFPA) provides free-to-view access to their wide selection of codes and standards, many of which include performance-based options. The NFPA also provides access to free data and research reports on fire topics including fire and sustainability interactions in a number of areas (e.g., PVS, ESS, EVs, etc.)

Performance-Based Analysis and Design Research

The U.S. National Institute of Standards and Technology (NIST) conducts and supports research in a variety of building performance areas, including energy / high-performance buildings, fire performance of buildings, structural performance of buildings, and resilient buildings and communities.  Publications on NIST research can be found through their publications site.

Internationally, there are numerous research institutions which conduct and support building performance research. We note just a few here where publications are freely available.

Also, universities across the U.S. and around the world publish research reports, PhD and MS theses, and other such research documents.

Performance Analysis, Design Standards and Guidelines
(purchase may be required)

Several professional societies and associations publish performance-based design standards or guidance. Many of these are only available for purchase. We list a few US-based entities below.

More Performance Code Resources and Activities

YouTube Channel
(Coming Soon)

Online Resources
(Coming Soon)

Useful Websites

PMG Code Action Committee (PMGCAC)

The Plumbing Mechanical and Fuel Gas Code Action Committee (PMGCAC) meetings are open to the public. Any interested party can participate in committee meetings and can be considered by the committee for membership on any sub-group that the committee creates. Interested parties will be notified by email of PMGCAC activities including committee meetings, sub-group meetings and the availability of PMGCAC related documentation. If you wish to be placed on the “interested parties” list for the PMGCAC, contact the ICC Secretariat, Fred Grable.

See Council Policy 31 "Code Action Committees" for the scope of each of the CAC's.

Committee Document(s)

Click on a document type and then click on the PDF icon to view document(s).

For archives on the past PMGCAC work, click here.

2021 IECC – A Code on a Mission

2021 IECC: A Code on a Mission

States and localities have set either greenhouse gas (GHG) reduction goals or established zero-energy building targets. The U.S. Administration has set zero-energy building goals of 2030 for new construction and 2050 for all buildings.

National, state and local governments cannot meet their GHG reduction goals without addressing buildings and thus having building energy codes that align with the goals.

The International Code Council is launching the Code on a Mission challenge to get over a third of the U.S. population covered by energy codes based on the 2021 IECC by the end of 2023.

Check this page regularly to find out how we are progressing in meeting our goal. We also have resources, including a fact sheet,  that can be shared to promote the benefits of the adoption and implementation of the 2021 IECC.

Supporting Organizations


ICCPC – Reimagine the ICCPC | Join The Conversation

Reimagining the ICC Performance Code

Reimagining the ICC Performance Code

Performance-based design has both advanced and grown in popularity over the past few decades, and many countries have successfully embraced performance-, objective- and function-based building regulations.

In order to provide a modern, updated International Code-based option available to those interested in an updated performance-based code, the International Code Council is embarking on a process to rethink the ICC Performance Code for Buildings and Facilities (ICCPC), a code that was first developed in the 1996–2000 code cycle and has had very few revisions since.

With the help of Meacham Associates, we are seeking to understand current thinking and perspectives across numerous disciplines about how performance-based approaches are viewed, what can and should be done to make them more robust to achieve a high level of confidence in the code, design approaches, tools, methods and data, designs that are developed.

Stage Icons LG V1 People3
Stage Icons V1 Survey2

Stage 1: Undertake broad sector-wide surveys and targeted workshops among stakeholders, including those currently using performance-based codes and those interested in having more performance-driven options in building codes.

Stage Icons V1 Outline

Stage 2: Develop an outline of the essential components of a modernized performance code that embodies current thinking in the U.S., global experiences and best practices, existing and emerging societal expectations for building performance, and existing and emerging data, tools, methods, materials and systems.

Stage Icons V1 Globe2

Stage 3: Recommend changes to improve and modernize the ICCPC – which could be significant in terms of structure, approach and content – to increase the appeal of its use in jurisdictions around the world, including in the United States.

More Performance Code Resources and Activities

More Icons V1 Youtube1

YouTube Channel
(Coming Soon)

More Icons V1 Onl Resources

Online Resources
(Coming Soon)

If you have questions, ideas, or need clarifications, please reach out to us at performance@iccsafe.org.



The International Organization for Standardization (ISO) is an independent, non-governmental international organization with a membership of 165 national standards bodies. Through its members, it brings together experts to share knowledge and develop voluntary, consensus-based, market relevant International Standards that support innovation and provide solutions to global challenges.

For the U.S., the American National Standards Institute (ANSI) is the national representative to ISO. ANSI relies on member standards development organizations to assure that U.S. interests are represented in the technical work of ISO. The International Code Council is accredited by ANSI to administer the U.S. Technical Advisory Group (US TAG) to the International Organization for Standardization Technical Committee 59 (ISO/TC 59): Buildings and Civil Engineering Works.

About ISO/TC 59

ISO Technical Committee 59 develops international standards in the field of Buildings and Civil Engineering Works. ISO/TC 59 standards include but are not limited to those of:

  • General terminology
  • Organization of information in the processes of design, manufacture and construction
  • General geometric requirements for buildings, building elements and components including modular coordination and its basic principles, general rules for joints, tolerance and fits, performance and test standards for sealants
  • General rules for other performance requirements, including functional and user requirements related to service life, sustainability, accessibility and usability
  • General rules and guidelines for addressing the economic, environmental and social impacts and aspects related to sustainable development;
  • Geometric and performance requirements for components that are not in the scope of separate ISO technical committee
  • Procurements processes, methods and procedures

ISO/TC 59 is organized into nine sub-committees:

  • TC 59/SC 2 Terminology and harmonization of languages
  • TC 59/SC 8 Sealants
  • TC 59/SC 13 Organization and digitization of information about buildings and civil engineering works, including building information modeling (BIM)
  • TC 59/SC 14 Design life
  • TC 59/SC 15 Framework for the description of housing performance
  • TC 59/SC 16 Accessibility and usability of the built environment
  • TC 59/SC 17 Sustainability in buildings and civil engineering works
  • TC 59/SC 18 Construction procurement
  • TC 59/SC 19 Prefabricated building

U.S. Participation in ISO/TC 59

What is a U.S. Technical Advisory Group?

U.S. technical experts to the ISO Technical Committees are organized into Technical Advisory Groups (TAG), which formulate the U.S. position on ISO TC matters. These positions are formally submitted by ANSI, as the U.S. voting member to the International Organization for Standardization (ISO).

Any individual or organization based in the United States of America that has an interest in standards development is encouraged to participate through the ANSI accredited Technical Advisory Group (TAG). U.S. Representatives interested in participating in the TC 59 U.S. TAG should complete the Membership Application.

As TC 59 considers the development and approval of new standards and the establishment of new subcommittees and working groups, the U.S. TAG can weigh in to assure that U.S. interests are represented.

Participating in the U.S. TAG to ISO/TC 59

The construction industry is constantly being challenged with demands of higher effectiveness and better profitability, and new demands emerge as globalization and international trade expand. The standards developed under ISO/TC 59 address these demands and benefit the entire industry. They also provide frameworks that other construction-related committees at ISO can build on in their work.

Participating in international standards development is one of the best ways to stay informed and build close mutually beneficial relationships with companies around the world. It also assures that international standards reflect the specific needs of U.S. industry and avoid unnecessary duplication or conflict. Participation in the U.S. TAG is open to all U.S. national interested parties who are directly and materially affected by the TAG’s activity.

There are many advantages to joining the U.S. TAG to TC 59.  As a member, you will:

  • Shape the future of your industry by lending expertise to the creation of building and civil engineering standards that will affect your business and international trade
  • Benchmark your company’s position in the global marketplace
  • Have access to documents at all stages of the process
  • Network with peers from around the world

While the International Code Council is the ANSI accredited administrator of the U.S. TAG to TC 59, several other U.S. SDOs participate as ANSI accredited administrators to some of the TC 59 subcommittees. ASTM International is the ANSI accredited administrator to SC 8 and SC17, and ASHRAE is the ANSI accredited administrator to SC13. The U.S. does not currently participate in the other subcommittees.


For more information contact the TAG Administrator.

IECC/HERS Compliance

IECC/HERS Compliance Specialist Designation

The International Code Council is pleased to announce a new combination designation, the IECC/HERS Compliance Specialist. You must be a current RESNET HERS Rater or Rating Field Inspector (RFI) and hold the Residential Energy Inspector/Plans Examiner Certification (79).

Learn more becoming an IECC/HERS Compliance Specialist

Why you should work with an IECC/HERS Compliance Specialist

Become an IECC/HERS Compliance Specialist

This designation combines the energy code knowledge of code officials with the energy efficiency knowledge of HERS Raters to identify experts in energy plan review and inspection. The credential leverages the strengths of both organizations to increase the number of qualified individuals available for evaluating energy code compliance and home energy performance.

The IECC/HERS Compliance Specialist designation verifies competence in energy performance measurement and energy code proficiency. These certified specialists can supplement the work of jurisdictions facing resource constraints that affect their ability to conduct the necessary reviews. IECC/HERS Compliance Specialists may now be used for both code compliance and energy performance rating services.

Frequently Asked Questions

To obtain this combination designation, you must meet the following requirements:

  1. be a current RESNET HERS rater or Rating Field Inspector (RFI)
  2. and hold a 79 - Residential Energy Inspector/Plans Examiner

If you hold an active G8 Energy Code Specialist Designation, this may be used in place of the 79.


Why Hire IECC/HERS Compliance Specialists?

You Can Feel Secure
with Verification of Energy Code Compliance!

  • Inspectors have demonstrated knowledge through certifications from RESNET and ICC.
  • Inspectors credentialed from RESNET and ICC through new IECC/HERS Compliance Specialist designation for HERS Raters that pass the ICC Residential Energy Inspector/Plans Examiner certification exam.
  • ICC certifications and HERS Raters subject to stringent RESNET Quality Assurance oversight.
  • Transparency through new Code Officials Dashboard via the RESNET National Buildings Registry (Coming Soon)

You Can Save Time
on Energy Code Review and Approval!

A recent US Department of Energy commissioned study, conducted with assistance from ICC, found that code officials spend an average of 4.5 hours reviewing performance compliance submittals.

When IECC/HERS Compliance Specialists conduct performance energy code compliance, code officials can quickly review and approve submittals knowing that qualified individuals certified by ICC in Residential Inspections and Plan Reviews were behind them.