Installing reflective insulation is similar to placing batts and blankets. Proper installation is very important if the insulation is to be effective. Study and follow the manufacturer's instructions. Often, reflective insulation materials have flanges that are to be stapled to joists in attics or floors, or to wall studs. Since reflective foil will conduct electricity, one must avoid making contact with any bare electrical wiring.
Radiant barriers may be installed in attics in several configurations. The radiant barrier is most often attached near the roof, to the bottom surface of the attic truss chords or rafter framing. The Attic Radiant Barrier Fact Sheet published by the US Department of Energy shows which parts of the country are most likely to benefit from this type of system.