In the past there have been concerns expressed that it was more difficult for smaller sized homes to achieve lower HERS® Index scores than it is for larger homes. To address this issue, the RESNET Standards Development Committee 300 authorized the release of a proposed standard amendment that incorporates a house size adjustment factor (BSR/RESNET/ICC 301-2014 Addendum E-201x, draft PDS-05).The Addendum was out for public comment from November 10, 2017 to December 10, 2017. As of February 1, 2018 this Addendum has been approved. The purpose of the amendment is to incorporate adjustments for dwelling size in Energy Rating Index calculations. Current Energy Rating Index standard calculations result in a discrepancy in the rating index for large versus small dwellings similarly equipped and configured for energy efficiency. Larger dwellings have lower rating index numbers than smaller dwellings. The purpose of the amendment is to establish a calculation methodology that compensates for size in order that similarly configured and equipped dwellings of different sizes will have equivalent ratings.To view the addendum, click on ANSI/RESNET/ICC 301-2014 Addendum E-2018 House Size Index Adjustment Factors (IAF). To view comments click submitted for the standard click on BSR/RESNET/ICC 301-2014 Addendum E-201x, draft PDS-05, Index Adjustment Factors Comments.
