Thermal performance is a very important issue. State governments, local jurisdictions and utility companies are requiring higher thermal performance ratings on all duct insulation. As the industry leader, we’ve taken an active role in developing industry stanfards and supplying you with the flex duct that has varying R-values classified by Underwriters Laboratories Inc. and the ADC(Air Diffusion Council) Seal of Certification. When installed properly, ATCO’s flexible ducts are very energy efficient. They create an airtight duct system that distributes the conditioned air to the living area, with virtually no leakage and minimal heat gain/loss.