In which location are radiant barriers typically installed?

• A. In attics.
• B. Under slabs.
• C. Behind interior drywall.
• D. Inside walls.

Answer: (A)

Radiant barriers work by reflecting infrared heat rather than absorbing it, which helps keep the space cooler. They are placed where roof heat accumulates—the attic—so they can intercept the sun’s radiant energy before it heats the attic air and, in turn, the living spaces. The attic is ideal because the roof directly receives solar radiation, creating a large surface area that can reflect heat back outward when a reflective barrier is installed with a proper air gap.

Under slabs, behind interior drywall, or inside walls don’t sit in the sun-facing path of roof radiation and aren’t arranged to maintain the necessary air space for the barrier to function effectively.