A radiant barrier is a surface that uses its reflectivity to reflect radiant heat, as opposed to regular surfaces, which absorb it. This effect reduces the overall gained heat and, correspondingly, reduces cooling expenses. Basically, a radiant barrier reflects the sun’s thermal energy away from a building, helping to negate it’s heating effect.
Expanding upon this concept; radiant barriers specialize in inhibiting heating by reducing heat transfer through thermal radiation. There are three main ways heat can be transferred; thermal radiation, convection, and conduction. Thermal radiation is generated by the motion of particles; using a radiant barrier helps reflect these particles. Conduction is heat transfer due to particle collisions and convection is heat transfer due to fluid movement. By definition, a radiant barrier reflects thermal radiation; to mitigate the other two forms all that needs to be done is to add insulation behind the barrier. This results in a cooling surface that is outstandingly effective as it addresses all three of the major forms of heat transfer. To achieve this setup, there are a few guidelines that should be followed. First, a radiant barrier should be installed pointing outwards into open air space. Then, a normal insulation such as fiberglass can be fit into place behind the barrier. Regarding materials for the barrier; the main requirement is that it should have low reflectivity or emissivity. An example that meets this condition is aluminum foil. The foil is usually attached to cardboard or some other material to increase its durability and allow for easy installing.
Particularly in humid climates such as Houston, an insulated radiant barrier can be very successful in reducing heat transfers and, therefore, cooling costs. One of the premier companies that is capable of installing radiant barriers is Triple Seal Insulation. With installation available quickly, there is virtually no reason not to make use of radiant barriers.