HVAC FOR BEGINNERS Ductwork is the channel through which the air in your home is filtered and purified, or expelled to the outdoors and replaced with fresh new air. Each component of the ducted air delivery system, from the air handler to the registers, adds a certain amount of resistance to the airflow.HVAC Beginners Ductwork · Do-It-Yourself Videos of ductwork schematics Click to view on YouTube12:41Quick and Easy Duct Design Information214K views · 2 years agoYouTube › David JonesClick to view on YouTube17:39Ductwork sizing, calculation and design for efficiency - HVAC Basics + full worked example142K views · 1 year agoYouTube › The Engineering MindsetClick to view on YouTube19:24How to Read HVAC Schematic Drawings - ENGINEERS CENTER18K views · 3 years agoYouTube › Engineers CenterSee more videos of ductwork schematics Do It Yourself Hvac Our example home is typical 1000 square feet with an unfinished basement. The ductwork (sheet metal duct) in this style home is usually fairly easy and straight-forward. Do It Yourself Hvac: The Design. A proper design must be performed to determine your furnace, air conditioner, and duct sizing.