> Hart&Cooley. SUBMITTER DRAWING install confidence METABOLIZED VAPOR BARRIER INSULATION RIGID DUCT (NOT INCLUDED) STARTER CONE SLEEVE IS SHOWN INSTALLED THERMAL CHARACTERISTICS *R-value of B.0 when measured per MAST C518 at 75°F mean temperature based on insulating same duct size. «2.5 inch thick, 0.75 PCF density glass fiber insulation has a C factor of 0.