ANSI/CRRC S100 Standard

Last page update: November 13, 2026

The current edition of ANSI/CRRC S100 - “Standard Test Methods for Determining Radiative Properties of Materials” was approved by the American National Standards Institute (ANSI) on December 5, 2024. The standard covers test specimen preparation and test methods for measuring the initial and aged radiative properties of roofing and exterior wall products. The standard is referenced by building codes and rating programs worldwide in order to measure the initial and aged solar reflectance and thermal emittance of roofing and exterior wall materials.
 

Last Update of CRRC S100 Standard

The CRRC S100 standard was revised in accordance with CRRC and ANSI requirements. The CRRC Consensus Body, a balanced group of 24 individuals spanning three interest categories (Users, Producers, and General Interest), evaluated proposed revisions and comments on the draft standard over a year-long process. After two rounds of public review, the draft standard was approved by the Consensus Body, CRRC Board of Directors, and ANSI in late 2024.

Next Update of CRRC S100 Standard

The Cool Roof Rating Council (CRRC) is commencing a revision of CRRC S100-2025, and seeks applicants for the Consensus Body. The Consensus Body is the committee responsible for evaluating proposed changes and public comments on the draft revised standard. 

The Consensus Body is a balanced group of stakeholders representing three distinct interest categories: 

1. Users of the CRRC Product Rating Programs or CRRC S100 standard that specify roofing or exterior wall products for installation, for regulatory purposes, or for a voluntary program. This category includes building owners, facilities personnel, government agencies that use a CRRC Product Rating Program or CRRC S100 as the basis for regulation, organizations that have green building certification programs or rebate programs, specifiers, consultants, contractors, and building inspectors. This category also includes organizations that provide testing and weathering services (e.g., Accredited Independent Testing Laboratories and Approved Test Farms).
    
2. Producers, which are companies that produce or sell roofing or exterior wall materials, as well as the associations that represent those companies; and
    
3. General Interest, which are entities that do not use the CRRC Product Rating Programs or CRRC S100, and do not produce or sell roofing or exterior wall materials. This category includes independent research organizations, government agencies with an interest in energy or environmental issues (but do not establish or adopt regulations pertaining to cool roofs), non-profit organizations, and other organizations that do not directly profit from roofing product sales, but have a general interest in cool surfaces, energy sustainability, green building practices, and other related issues.

Apply for the Consensus Body 

Membership on the Consensus Body is open to all interested parties and is not limited to CRRC members. Membership to any organization is also not a requirement for serving on the Consensus Body. Knowledge of or familiarity with CRRC Product Rating Programs, CRRC S100, or a technical understanding of the concepts covered in the standard are desirable attributes but not mandatory requisites. 

Consensus Body members must be able to make the following time commitments during the during the standard development period (12–24 months):

• Review all proposed changes to the draft CRRC S100
• Review proposals submitted by the public
• Participate in at least three (3) two-hour virtual meetings
• Submit ballots on time

If you would like to apply for the Consensus Body, please complete the CRRC S100 Consensus Body Application by December 16, 2026.

The CRRC Standards Committee will evaluate all application materials and will accept between 12–24 candidates for the Consensus Body in accordance with the CRRC Standards Procedures. Applicants will be notified by January 4, 2027 of whether or not they have been accepted to the Consensus Body.

To learn more about the Consensus Body and the process to revise the CRRC S100, view the CRRC Standards Procedures.

The CRRC became an ANSI-Accredited Standards Developer Organization in 2008. After a three-year standards development process, the first edition of “ANSI/CRRC S100 - Standard Test Methods for Determining Radiative Properties of Materials” (formerly CRRC-1 Standard) was approved on November 16, 2010. The standard is currently in its fifth edition (approved by ANSI on December 5, 2024).

The ANSI Essential Requirements and the CRRC's procedures specify that the process for standards development must be a collaborative, balanced, and consensus-based approval process. As such, every few years the standard must go through a public review process. As part of this process, consensus must be reached by representatives from materially-affected and interested parties. The ANSI/CRRC S100 standard was developed with input from the public and the CRRC Consensus Body, a balanced group representing diverse interests, ensuring that all aspects of the standard are considered.

The ANSI/CRRC S100 standard covers test specimen preparation and test methods for measuring the initial and aged radiative properties of roofing and exterior wall products. The standard is referenced by building codes and rating programs worldwide in order to measure the initial and aged solar reflectance and thermal emittance of roofing and exterior wall materials.