rFOIL will stop 97% of Radiant Energy (heat that is radiating through the air in its direction). Radiant heat is often overlooked and misunderstood, often because R-Values do not take it into account. Radiant heat transfer is responsible for up to 75% of total building heat gain or loss. Traditional Insulation products such as fibreglass, cellulose and EPS foam board are effective in reducing CONVECTION and CONDUCTIVE heat transfer, but do little to prevent RADIANT heat transfer. Radiant heat energy can either be absorbed or reflected. rFOIL contains aluminum, which has an excellent reflective surface that effectively redirects this energy component.