They can cool the attic … but at what risk to the structure and the occupants? Could radiant barriers represent a potential for harm?
Read the McDowell Owens Engineering Inc. white paper as to how “The physical and electrical properties of these materials are such that they introduce new and very serious dangers of ignition and fire.”
The link that I had used for years to the original McDowell Owens Engineering Inc. report is no longer operating; however, you can find a pdf copy of the report by clicking here.
The summary of the McDowell Owens Engineering study is, as follows:
“1. Standard installation methods for roof sheathing with integrated radiant barrier are such that the end result is an overall environment where all of the radiant barrier material and virtually everything metal on and around the roof are electrically connected.
“2. In most cases, something in that environment is connected to earth ground. If anything in the roof environment becomes electrically energized (by lightning or any other common source) there is a high probability the current will pass through the barrier material at some point on the way to earth ground.
“3. The physical and electrical properties of reflective radiant barrier materials which we tested are such that the material in a structure provides two new and unique hazards relative to fire causation.
(a) When energized by an electrical current the material readily generates temperatures sufficient to ignite MANY materials.
(b) The barrier material itself readily serves as the first ignited material.”
If you are considering radiant barriers as an energy efficiency upgrade … if you reside in a home with radiant barriers that are installed … if you are considering a recommendation by an energy auditor or other entity to install them … read this report, first.