1.1 ,Purpose—,The purpose of this guide is to define a commercially useful standard in the United States of America for incorporating building energy performance into an assessment of existing property condition, and specifically into a property condition assessment (PCA) on a building involved in a commercial real estate transaction. The guide is intended to provide a methodology for the user to identify building energy under-performance compared to peer buildings. If the building is under-performing compared to its peers, a methodology is provided to identify potential energy performance improvements and provide a probable cost for such improvements. The guide may be used independently or as a voluntary supplement to ASTM Guide E2018 PCA. Utilization of this guide and incorporating it into a PCA is voluntary. If the property owner is unwilling or unable to provide building energy consumption information and it is not possible to develop a reasonable estimate of building energy consumption, the methodology defined by this guide cannot be performed.