There is simply no duct like it in the world. Thermaduct combines the best of air distribution technology with choice outdoor weather barrier to create a duct that offers the highest R value and lowest air leakage rates in the industry. Unsurpassed performance was the goal to create a duct that can not only deliver every cubic foot of air it is fed, but to treat the air with the utmost respect by not exposing it to fibrous or volatile organic chemical latent liners. Indoor, the air passes a smooth aluminum surface that is clad to Kingspan's Kooltherm closed cell rigid thermoset resin insulated core. The outer layers include factory autohesively bonded FSK aluminum with a UV stable, 39 mil, titanium infused vinyl that is vacuum pressed and laminated permanently to Kingspan KoolDuct. Air distribution segments are connected together with either 4-bolt flange, aluminum channels OR cohesively bonded vinyl couplings. Once installed, all seams are sealed completely for uncompromising integrity and one of the best outdoor duct warranties in the industry.