Performance of buildings depends upon building envelope, Heating Ventilation and Air-conditioning system, lighting system, and Domestic Hot Water services. This book gives idea to improve indoor thermal environmental conditions by implementing Buildings Codes such as Energy Conservation Building Code (ECBC) and ASHRAE 90.1 Standard. Building consumes about 40% of total energy and therefore it is a need of time to improve their efficiency by employing codes and others measures/techniques. Code compliance Building consume less than 40% of energy compare to conventional practiced buildings....