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Draft PDS-01, BSR/RESNET/ICC 301-2019 Addendum D-202x, CO2 Rating Index

The RESNET Board of Directors established the Load Flexibility Task Group in 2019 and one of the assigned tasks was:

    1. The TG should evaluate energy consumption impacts such as carbon emissions using local factors and offering more than one key index.

The Task Group developed the proposed revision of Standard ANSI/RESNET/ICC 301-2019 based on the following concept. SDC 300 has considered the proposal and approved draft PDS-01 Addendum D for public comment.



  • Create CO2 Rating Index using hourly energy simulation results from accredited HERS® tools
  • Use NREL Cambium database year 2050, Low RE Cost-case, Long-Run Marginal, hourly CO2 emission factors applied against electric energy consumption
  • Use EPA AP-42 for Emission Factors applied against household combustion fuels (e.g. natural gas, fuel oil, propane)
  • Make no alterations to the calculation of the HERS® Index/ERI
  • Configure the CO2 Rating Index Reference Home the same as the Energy Rating Reference Home except using electricity for all energy end uses.


This first draft of proposed Addendum D is submitted for public comment for 30 days, beginning August 27, 2021 and ending September 26, 2021. Only the changes shown by strike-through and underline text in red print are open for comment. To review and comment on the Draft follow the links below.

Draft PDS-01, BSR/RESNET/ICC 301-2019 Addendum D-202x

Comment on Draft PDS-01, BSR/RESNET/ICC 301-2019 Addendum D-202x

View comments on Draft PDS-01, BSR/RESNET/ICC 301-2019 Addendum D-202x


Tips and Reminders for Submitting Public Comments 

  • Comments must pertain to text in draft PDS-01 that is shown as either strikethrough or underlined and red print. Comments on portions of draft PDS-01 where no change is indicated will be rejected.
  • Comments must include a specific proposed change to the text of the draft open for comment. Proposed added text must be underlined and text proposed to be removed must be shown using strike-through. If not submitted in this format, the public comment may be rejected.
  • Do not submit comments on standards other than this one that is out for public comment.
  • If you submit public comment representing the collective interests of a group of stakeholders, you are encouraged to submit ONE public comment and identify all stakeholders in that comment. While not required, this expedites the ability of the committees to respond to commenters in a timely manner.
  • Public comments are reviewed by committees with volunteer members, that are Raters, Providers, Software Developers and other industry and public interest stakeholders. They are not reviewed by RESNET Staff.
  • Most amendments to RESNET standards are proposed by industry and public stakeholders not RESNET. To learn more about submitting proposed amendments visit this page:https://www.resnet.us/about/standards/submit-proposed-amendments/