As 90.1-2007 is essentially a compilation of addenda, we assume it may be treated in the way outlined in the footnote to EA prerequisite 2, "Project teams wishing to use ASHRAE approved addenda for the purposes of this credit may do so at their discretion. Addenda must be applied consistently across all LEED credits." However, between 2004 and 2007 Appendix G was modified in some ways without addenda being published or approved, and these modifications were made official only by inclusion in the 2007 version. We further assume that we can use these modifications, as long as we use ALL the modifications in the 2007 Appendix G and referenced sections of 90.1, similar to the guidance on addenda noted above. Is this correct?
For LEED v2.x Rating Systems, where ASHRAE 90.1-2004 is the referenced standard, it is acceptable to use ASHRAE 90.1-2007 Appendix G in place of ASHRAE 90.1-2004 Appendix G if the energy simulation follows the language of 2007 Appendix G in its entirety, though the project must only meet the prescriptive requirements listed in 2004. Projects that want to use 90.1-2007 in its entirety may do so as well. Applicable internationally.