AN UNBIASED VIEW OF ALUMINIUM FOIL INSULATION

What I have noticed is the insulated flex is stated as duct, as well as the foil uninsulated flex is outlined as an air connector (if mentioned in the slightest degree). In both case, the product has to be Ul 181 approved as a way to be used.Every single producer of flex has there own friction price duct calculator that has to be Utilized in sizing