Utility consumption data can be analyzed into components closely related to building systems. Weather sensitive and non weather sensitive components are normally separated by correlation of variable base degree-days and fuel or electricity use. The energy thus assigned to each component is a useful guide to the energy auditor in conducting a site visit. For example, if the extra use of electricity in summer appears normal then minimal consideration need be given to mechanical cooling equipment. Procedures used for such component analyses of 2,500 buildings are presented. Extra information gleaned from such analyses for 17 schools is compared with field conditions, and its impact on site surveys is discussed. Data are shown for conditions before and after an energy conservation program.