Secondary Author(s)

Vieira, Robin

Report Number




Building Codes


The EnergyGauge® USA (v.6.2) residential building energy simulation software tool is used to examine energy impacts in two-story, 2,376 ft2, single-family homes configured in accordance with the minimum requirements of Section R402-R404 of the 2018 IECC in fourteen representative U.S. cities.4 EnergyGauge USA is a RESNET-accredited HERS software tool capable of evaluating not only the HERS Index and the IECC Section R406 Energy Rating Index Compliance Alternative but also the IECC Section R405 Simulated Performance Alternative as well as the IECC Section R402 R-Value and Total UA Alternative prescriptive methods along with all of the IECC mandatory minimum requirements of all of these compliance methods.

Simulations for each home prototype are conducted using three foundation types: Slab-on-grade (SOG), crawlspace and basement. For each prototype and foundation type, each of the IECC compliance methods are evaluated on the basis of pass/fail and on the basis of performance comparison. For example, where the code evaluation is via the Total UA Alternative, the IECC baseline Total UA value is compared against the prototype Total UA value to determine the compliance ratio between the prototype and the IECC baseline. Similar comparison is conducted for the R405 Simulated Performance Alternative. Additionally, the R406 Energy Rating Index Compliance Alternative (ERI) is compared against the HERS Index for each prototype and each foundation configuration.

Date Published


Local Subjects

Buildings - Building Codes


FSEC Energy Research Center® Collection



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