What is a Home Energy Rating?

The home energy rating is a standard of measurement of the home's energy efficiency.  An energy rating allows a home buyer to easily compare costs for the homes being considered.

What's involved in a Home Energy Rating?

Your home's energy rating involes an AEA analysis of your home's computer generated building model (or construction plans for new homes), onsite inspections and off-site data analysis.  If your plans are not available, we recreate them.  Based on the home's plans, your AEA Home Energy Rater uses the REM/Rate software package to perform an energy analysis of the home's design.  This analysis yields an existing pre-improvement HERS Index (or pre-construction HERS Index if it is a new home).  Upon completion of the building model or plan review, your AEA Rater will work with you to identify the energy efficiency improvements needed to ensure the home will meet ENERGY STAR® performance guidelines.  Your AEA rater then conducts several onsite inspections and tests, typically including a blower door test (to test the leakiness of the house) and a duct tests (to test the leakiness of the ducts).  Results of these tests, along with inputs derived from the building review, are you used to generate the HERS Index score for the home.  Once enough improvements have been made to reduce your score to which is determined by the new VERSION 2.5 and VERSION 3.0 giudlines, your house will be listed by the EPA as an ENERGY STAR home, you are awarded an ENERGY STAR certificate and an ENERGY STAR label is attached to your home's electrical panel.

The HERS (Home Energy Rating System) Index

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.

Each 1-point decrease in the HERS Index corresponds to a 1% reduction in energy consumption compared to the HERS Reference Home.  So a home with a HERS Index of 85 is 15% more energy efficient than the HERS Reference Home and a home with a HERS Index of 80 is 20% more energy efficient, and so on.