Contains requirements for the reference building to which the actual building design must be compared. In Section 8.7.1, the ducts assumed for the reference building must be completely within the conditioned space. In much of the country where ducts are commonly located in unconditioned spaces, this requirement represents a disincentive to use the performance path of Section 8. The prescriptive requirements for buildings with ducts in unconditioned spaces are more stringent than those for buildings with ducts in the interior. Given the current understanding of the issue, the prescriptive requirements cannot be assumed to reflect the real impact of duct losses. To provide an incentive to move ducts indoors, the performance path must acknowledge the reality that ducts are commonly located in unconditioned spaces. The change will benefit builders who typically locate ducts in conditioned spaces and increase the benefits of the performance path. For those who typically locate ducts in unconditioned spaces, the proposed change will provide a strong incentive to move ducts inside.The change in Section 8.7.6 to the assumption of wood doors for the reference case removes a penalty for using the performance path, while recognizing the common practice of using wood entry doors.This standard was listed for public review in the 8/15/1997 issue of Standards Action. It is being resubmitted due to substantive changes to the text.