What is Radiant Barrier and how does it work?
Radiant barriers or reflective barriers are aluminum foil reflective materials installed in residential or commercial attics to reflect heat, reducing the temperature to ducts and insulation located below the radiant barrier. Radiant barrier works by reducing heat transfer by thermal radiation. All materials give off, or emit, energy by thermal radiation as a result of their temperature. The amount of energy emitted depends on the surface temperature and a property called the emissivity (also called the “emittance”). The emissivity is a number between zero (0) and one (1). The higher the emissivity, the greater the emitted radiation. A closely related material property is the reflectivity (also called the “reflectance”). This is a measure of how much radiant heat is reflected by a material. The reflectivity is also a number between 0 and 1 (or a percentage between 0 and 100%). For a material that is opaque (that is, it does not allow radiation to pass directly through it), when the emi
