Zero Energy Performance Index (zEPI)

Factsheet / June 30, 2015 / Codes And Policy, Getting to Zero

The 2015 International Green Construction Code (IgCC) includes many progressive measures that will improve the energy performance of buildings. One important provision describes the Zero Energy Performance Index (zEPI), which provides a scale for measuring commercial building energy performance. This factsheet describes zEPI's representation of a fundamental shift in measurement of building efficiency as it sets energy targets for actual energy consumption rather than using a predictive energy model of building energy performance to calculate a “percent better than code” metric. zEPI sets an energy use intensity (EUI) target for building type and is adjusted for climate. It is also the measure by which a building’s energy efficiency is calculated once operational and occupied based on measured energy use data.