Buildings account for almost half of total primary energy use and related greenhouse emissions worldwide. Although current energy systems are improving, they still fall disappointingly short of meeting acceptable limits for efficiency. Well-trained energy auditors are essential to the success of building energy efficiency programs—and Energy Audit of Building Systems: An Engineering Approach, Second Edition updates a bestselling guide to helping them improve their craft. This book outlines a systematic, proven strategy to employ analysis methods to assess the effectiveness of a wide range of technologies and techniques that can save energy and reduce operating costs in residential and commercial buildings. Useful to auditors, managers, and students of energy systems, material is organized into 17 self-contained chapters, each detailing a specific building subsystem or energy efficiency technology. Rooted in established engineering principles, this volume: Explores state-of-the-art techniques and technologies to reduce energy consumption in buildings Lays out innovative energy efficiency technologies and strategies, as well as more established methods, to estimate energy savings from conservation measures Provides several calculation examples to outline applications of methods To help readers execute and optimize real building energy audits, the author presents several case studies of existing detailed energy audit reports. These include results from field testing, building energy simulation, and retrofit analysis of existing buildings, with recommendations based on sound economic analysis. Examining various subsystems, such as lighting, heating, and cooling systems, it provides an overview of basic engineering methods used to verify and measure actual energy savings attributed to energy efficiency projects. The author presents simplified calculation methods to evaluate their effectiveness and ultimately improve on them. Ideal either as a professional reference or a text for continuing education courses, this book fortifies readers’ understanding of building energy systems, paving the way for future breakthroughs.