How to Evaluate Sensitivity of an Attic Radiant Barrier

Determine a radiant barrier’s reflective sensitivity to heat rays. Locate the “reflectivity” rating on the product’s manufacturer data sheet. Reflectivity ratings indicate how well an attic barrier reflects radiant heat rays. Within an attic space, radiant heat is naturally absorbed into objects and surfaces. The objects and surfaces then radiate this heat out into the attic space.

Using a scale of 0 to 1.0, determine a radiant barrier's level of reflectivity. The closer the number is to 1.0, the stronger the barrier’s reflective capacity.

Determine a radiant barrier’s ability to emit, or conduct heat. Locate the “emissivity” rating on the product’s manufacturer data sheet. A radiant barrier’s emissivity rating indicates how easily heat can move through the barrier material.

Using a scale of 0 to 1.0, determine the attic barrier’s sensitivity to heat conduction. Because heat conduction increases the amount of heat in an attic space, the lower the number — or the closer it is to zero — the better. A low number indicates an attic barrier blocks heat from passing through.