Accurate Energy Modeling of Unvented Attics - Why it is important to the PU Industry

摘要

The American Chemistry Council-Center for Polyurethane Institute Spray Foam Coalition and ConSol recently completed an evaluation of the California Building Energy Code Compliance (CBECC), the only State-approved energy modeling software that builders can use to demonstrate compliance with the Building Energy Efficiency Standards (Title 24). This study showed that California's CBECC software significantly under-predicted the energy savings of unvented attics (UVAs) when using SPF insulation as compared to field measured performance of UVA and when compared to alternative efficiency measures. Users report similar issues with other US energy modeling software, and additional work is being done to evaluate the accuracy of SPF UVA modeling results in these programs. This paper provides details the results of these studies and the efforts made to improve energy modeling software to accurately evaluate unvented SPF attic designs.