A HERS rating, or Home Energy Rating System rating, is a standardized numeric score reflecting a home’s overall energy performance, calculated through a comprehensive assessment process that considers insulation, air sealing, mechanical systems, and other factors affecting total energy consumption.
This rating system, developed and maintained by the Residential Energy Services Network, provides a consistent, comparable metric that allows homes of different sizes, ages, and locations to be evaluated using the same standardized scoring approach.
Because the HERS rating scale uses a specific reference point, with lower scores indicating better energy performance, this system provides an intuitive way to communicate relative efficiency, similar in concept to how golf scoring works with lower numbers representing better performance.
What Does a HERS Rating Involve?
- A certified HERS rater conducting a comprehensive home assessment
- Evaluation of insulation, air sealing, and mechanical systems
- Blower door and duct leakage testing as part of the process
- A standardized numeric score reflecting overall performance
Why Is a HERS Rating Important?
The standardized HERS rating provides a consistent way to compare energy performance across different homes, useful both for homeowners evaluating a potential purchase and for builders demonstrating a new home’s efficiency credentials to prospective buyers. This standardization has made HERS ratings increasingly common in new home marketing and real estate listings, particularly for homes built to higher performance standards.
Because achieving a lower, better HERS score often requires meeting or exceeding various green building or energy code requirements, this rating can serve as a useful proxy for overall home quality and performance beyond just energy consumption alone.
HERS Rating vs. HERS Index
These terms are largely used interchangeably, both referring to the same standardized numeric energy performance score, with HERS Index being the more precise technical term for the specific numeric scale used within the broader HERS rating system.