Report Number




Buildings; Energy Efficiency


EnergyGauge® USA (v.4.0.00) is used to examine the cost effectiveness of high performance homes that are improved to significantly exceed the minimum requirements of the 2015 IECC. The objective of the study is to determine the maximum level of energy efficiency that can be considered cost effective to the consumer. For these purposes, it is the cost effectiveness of the entire package of measures that is considered by the analysis rather than the cost effectiveness of individual measures. Optimization and rank ordering of the individual improvement measures in the package is not considered by the analysis.

One-story 2,000 ft2, 3-bedroom and 2-story, 2,400 ft2, 3- bedroom single-family homes in thirteen representative TMY cities, representing 8 IECC climate zones, are considered by the analysis. The energy use of the high performance Improved Homes is compared against the 2015 IECC Code Homes and against the SSPC 90.2 Reference Homes.

Simulations for each home are conducted for both a best case home orientation and a worst case home orientation. Improvements to the 2015 IECC homes are made such that the cost effectiveness of the improved homes have a savings to investment ratio (SIR) between 1.00 and 1.10 in order to determine the maximum efficiency that can be considered cost effective to the consumer. The incremental savings and improvement costs are estimated as the difference between the 2015 IECC Code Home and the Improved Home. Economic cost effectiveness calculations are performed in accordance with Appendix A, as taken from Section 4.6, ANSI/RESNET 301-2014.

The analysis shows that significant energy efficiency improvements relative to the 2015 IECC can be cost effectively achieved in all 13 representative TMY cities for all of the home configurations under all of the conditions evaluated.

Date Published



Buildings - Energy Efficiency



Rights Statement

In Copyright