The ASHRAE 90.1 User's Manual is a comprehensive textbook authored by ASHRAE, focusing on engineering principles related to heating, ventilation, and air conditioning systems. Published in 2002, this trade paperback manual is designed for individuals in the construction and HVAC industries, providing guidance on efficiently designing and implementing sustainable buildings. With 338 pages, this manual covers essential topics in engineering and construction, making it a valuable resource for professionals looking to comply with ANSI/ASHRAE/IESNA Standard 90.1-2001 requirements.