PURPOSE: A flexible duct for an air conditioning pipe is provided to secure a blocking function from flame and smoke in the fire by coating the surface of the duct with fire-resistant resin. CONSTITUTION: A flexible duct for an air conditioning pipe is made of fiber glass(11). The flexible duct for an air conditioning pipe has a blocking function from flame and smoke in the fire by coating the surface of the duct with fire-resistant resin. An iron core(13) is gradually built in inside the tube-shaped fiberglass. An uneven portion(12) is formed on the surface of the tube-shaped fiberglass in regular intervals of pitches. A band fixing portion(14) is formed in the both edges of the duct. The band fixing portion is inserted into the out edge of a pipe.
