Air ducts are a necessity for most conventional home heating and cooling systems. Most of these are “forced-air” systems, meaning they use a blower fan and a set of air ducts to circulate cooled or warmed air throughout a building.
But not all homes are built with air ducts. Older homes, smaller spaces, or room additions in an existing home may be without ducts, and that means homeowners find varying solutions for heating and cooling—like portable AC and heat or noisy window units. But these are often inefficient and of a poor quality.