A Home Energy Rating involves an analysis of a home’s construction plans and onsite inspections. Based on the home’s plans, the Home Energy Rater uses (modeling software to project the homes energy performance based on the information provided) an energy efficiency software package to perform an energy analysis of the home’s design. This analysis yields a projected, pre-construction HERS Index score. The rater then conducts onsite inspections during construction. These include an insulation inspection prior to drywall, and a final inspection including a blower door test (to test the leakiness of the house) and if needed, a duct blaster test (to test the leakiness of the ducts). Results of these tests, along with inputs derived from the plan review, are used to generate the HERS Index score for the home.

Energy Modeling Software can also be used to certify that a newly constructed home qualifies for the $2000 Federal Tax Credit for a 50% reduction in heating demand compared to the HERS Reference Home. This may be an appealing goal for builders and homeowners.

The HERS Index is a scoring system established by the Residential Energy Services Network (RESNET) in which a home built to the specifications of the HERS Reference Home (based on the 2006 International Energy Conservation Code) scores a HERS Index of 100, while a net zero energy home scores a HERS Index of 0. The lower a home’s HERS Index, the more energy efficient it is in comparison to the HERS Reference Home.