All homes submitted on or after November 1, 2017 will be processed using the updated UDRH.
The latest version of the UDRH contains a single update related to the treatment of gable walls in sealed attics. Previous versions of the UDRH incorrectly assigned a low R-value to walls between sealed attics and ambient conditions. As a result, the reference home usage increased along with assigned savings.
The updated UDRH now uses the standard code level R-value for above-grade walls (per climate zone) when setting gable walls in sealed attics. Savings for homes with sealed attics will decrease if they have gable walls. As always, the program's intent is to drive accurate savings. In this case the reportable savings for a subset of homes will decrease.
Please begin using the updated UDRH at your earliest convenience to allow time for adjusting savings projections. In addition, any unexpected behavior should be reported to the Program ASAP.
Please feel free to contact us at DEPRNC@icfprogram.com with any questions.