ZELLTECH Insulation is a leading brand in the field of Radiant Heat Aluminum Foil Reflective Barriers for Roof Insulation and Vapor resistance for AC Duct ISOLATION. In summer, solar energy is absorbed by the roof, heating the roof covering and causing the underside of the roof casing and framing to radiate downward heat towards the attic floor. When a Radiant heat barrier is placed on the attic floor, much of the heat radiating from the master roof is reflected back onto the roof. This makes the upper surface of the insulating cooler so that it will be without a Radiant heat barrier and thus reduces the amount of heat moving through the insulation into the rooms below the ceiling.