EUI is the abbreviation for Energy Use Intensity, a key performance indicator that normalizes a building’s annual energy consumption by its square footage. This standardized metric enables meaningful comparisons between buildings of vastly different sizes and operational profiles. EUI is expressed in energy units per square foot annually, making it the foundation of energy policy and building performance standards.
Calculation and Standards
EUI is calculated by dividing total annual site energy consumption (in kilowatt-hours or Btu) by gross conditioned floor area. Weather normalization adjustments account for variations in heating and cooling degree days. The EPA Energy Star program uses EUI as a core metric, with buildings achieving scores of 75 or higher considered high performers.
Industry Significance
Municipalities increasingly mandate EUI disclosure and tracking through local building performance standards. This regulatory push has made EUI critical for real estate valuation, mortgage financing, and tenant leasing decisions. HVAC professionals use EUI targets to inform equipment selection, system design, and retrofit strategies that reduce a building’s energy footprint.