The heating, ventilation, and air-conditioning (HVAC) system is one of the more complex systems installed in a structure and is responsible for a substantial portion of the total structure energy use. Right-sizing of an HVAC system is the selection of equipment and the design of the air distribution system to meet the accurate predicted heating and cooling loads of the structure. Right-sizing the HVAC system begins with an accurate understanding of the heating and cooling loads on a space; however, a full HVAC design involves more than just the load estimate calculation; the load calculation is the first step of the iterative HVAC design procedure. This strategy guideline discusses the information needed to design the air distribution system to deliver the proper amount of conditioned air to a space. This course is not a procedural step-by-step set of instructions on duct design and air distribution, but rather a guideline to the considerations for duct design in an energy-efficient structure. Topics: HVAC System Performance Criteria Temperature Mixing and Uniformity Volume and Pressure of Air Ductwork Materials and Configuration Supply and Return Outlets Impact on Uniformity Throw, Spread, and the Coanda effect System Noise Reduction Integrated Design Design Principles Pressure Drop Room-by-Room Supply Requirements Return Air Design Duct Layout and Sizing Intended Audience: primarily for mechanical, facilities, civil, construction, chemical, and other engineers who may deal with HVAC and air flow within the parameters of their job. Publication Source: US Dept. of Energy