Insulating ductwork effectively prevents conditioned air from leaving into unconditioned areas like attics or crawlspaces

https://www.mediafire.com/file/trs88ymhpdawlin/pdf-93657-87655.pdf/file

Insulating ductwork appropriately avoids conditioned air from escaping into unconditioned areas like attics or crawlspaces, improving general system effectiveness and decreasing inefficient costs.