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The Building Energy Codes Program will have reduced staffing July 4 – July 8, 2024 for the Independence Day holiday weekend. Response times may be delayed. Please expect to receive responses after July 8, 2024.
This technical support document (TSD) is designed to explain the technical basis for the COMcheck software as originally developed based on the ANSI/ASHRAE/IES Standard 90.1-1989 (Standard 90.1-1989). Documentation for other national model codes and standards and specific state energy codes supported in COMcheck has been added to this report as appendices. These appendices are intended to provide technical documentation for features specific to the supported codes and for any changes made for state-specific codes that differ from the standard features that support compliance with the national model codes and standards. Beginning with COMcheck version 3.8.0, support for 90.1-1989, 90.1-1999, and the 1998 IECC and version 3.9.0 support for 2000 and 2001 IECC are no longer included, but those sections remain in this document for reference purposes.
This report explains the methodology used to develop version 4.6.5 of the REScheck software in order to support compliance determination for IECC editions 2009, 2012, 2015, and 2018.
