Is double sided Radiant Barrier any better than the single sided type?
• Yes, provided that it is installed with an air space on both sides. There are two properties which allow radiant barriers to work, reflectivity and low emissivity (low-e). Heat is reflected on the top/hot side, and since RB has a low-e value, heat is not emitted to the bottom/cold side. Of these two properties the low-e value is of greater importance. In order for a radiant barrier to be most effective in both summer and winter it needs to have aluminum on both sides. According to a study performed by a Texas A&M University professor, double sided radiant barriers were nearly 50% more effective than their single sided counterparts.
