The HERS Rating system (Home Energy Rating System Ratings) is a home energy rating and is a requirement for many green building and energy efficient building standards, and is the nation's leading set of guidelines. A HERS Rating assigns a score to the home being evaluated on a scale from 0-150, with lower numbers representing less energy consumption (a HERS score of 0 represents a "zero energy home," which produces at least as much energy as it consumes), and higher numbers representing greater energy consumption. A standard new home would receive a score of around 100, and most existing homes fall somewhere between 100 and 150.
Having your home rated can be a great way for builders and realtors to set their homes apart in a crowded real estate market -- a good HERS score is an objective, measured representation of a home's energy efficiency.
When purchasing or building a home an energy rating allows you to compare homes in relation to their energy efficiency.