The Home Energy Rating System (HERS) Index is the industry standard by which a home’s energy efficiency is measured. The HERS index is a nationally recognized system for inspecting and calculating a home’s energy performance and helps owners reduce the cost of their utility bills by making their homes more energy-efficient. Many SIP homes achieve HERS ratings of 50 or less, meaning they are at least 50% more energy-efficient than standard new homes. The airtight SIP building envelope and resulting HERS ratings help buildings qualification under various green building standards.
Government agencies such as the Department of Energy (DOE), Department of Housing and Urban Development (HUD) and the Environmental Protection Agency (EPA) recognize the HERS Index as an official verification of energy performance.
To calculate a home’s HERS Index Score, a certified RESNET Home Energy Rater will do a home energy rating and compare the data against a ‘reference home’ – a design modeled home of the same size and shape as the actual home, so the HERS Index Score is always relative to the size, shape and type of house you live in. The lower the number, the more energy-efficient the home.
A typical resale home represents 130 on the HERS Index while the reference home (a standard new home built in 2006) is rated at 100.
Click here to view a video on the basics of the HERS Rating Index.