Insulated flexible duct using compressible core spacer and method of use

A reflective insulating system-containing flexible duct comprising:

• an inner core having a defined length;
• a vapor barrier surrounding the cylindrical inner core;
• a compressible core spacer positioned between the inner core and vapor barrier, the compressible core spacer comprising a film material and helical support integrated with the film material, a length of the compressible core spacer longer than the defined length of the inner core, the compressible core spacer compressible in length when positioned between the inner core and vapor barrier, compression of the compressible core spacer folding film material between adjacent sections of the helical support, the film material when folded acting as a spacer to create a first air gap between an outer surface of the inner core and an inner surface of the compressible core spacer and a second air gap between the outer surface of the compressible core spacer and an inner surface of the vapor barrier;
• and
• at least one reflective insulation system comprising a low-E surface on one or more of the outer surface of the inner core, the inner surface of the compressible spacer, the outer surface of the compressible spacer, and an inner surface of the vapor barrier, the low-E surface in combination with one of the first or second air gaps forming the at least one reflective insulation system and increasing an R value of the flexible duct.