July 2012: Radiant Reflect Foil or Low E Insulation
We are beginning to see more and more contractors employ the use of this unique and versatile insulation product. It has numerous applications, meets flame and smoke spread tests, is non toxic and holds up to extremes of temperature ratings anywhere from -60 degrees F to 180 degrees F. The rated R value can range anywhere from approximately 7 to 10 based upon which plane the surface is aligned. The most important thing to realize is that these rated R values are determined with a ¼” continuous air space between the surface it is trying to insulate and itself. This means that anytime it is being used to insulate duct work or DHW tanks or doors that separation strips (3-4” in width) should be used to keep the material off of the intended surface to minimize direct conduction losses which may unintentionally cut the insulation value in about half.
Besides having an excellent fire rating, it comes in various sizes from 15” tabbed pieces to 24” to 48” rolls. It is easy to cut, mend and install and gives a smooth finished appearance. It also comes in multiple thicknesses with either two or three bubble layers or a more solid foam inner core. It can work fairly well when installed properly as an effective radiant barrier but all attempts should be made to seal and insulate the attic proper BEFORE investing money into an application where its intended use solely as a radiant barrier (findings were issued by Energy Vanguard where it was installed in a new house construction in Houston and only cut cooling load by about 3%). It can be used in many other applications such as: behind radiators, on garage door panels, on the back of exterior doors/hatches, backside of exterior returns, tight duct places, oversized pipes, as impromptu AC covers, DHW tanks and to upgrade attic hatch tent covers.