Reflective Insulation
It has two layers of aluminium foil, laminated to the outside. In building constructions our foils are hugely used for proving insulation. These help in reflecting heat hence warmth in winter and coolness in summer in building is maintained. Using these foils air-infiltration can be put to a stop and seals drafty building. Furthermore, it is also popular for vapor barrier qualities.
The rounded surface of the air bubbles keeps the two layers of foil separated and the individual bubbles, by trapping or enclosing air, ensure that there is a still-air insulating barrier between the two surfaces of foil, thus improving the R-value of the reflective insulating material. The bubble-trapped air means that no air movement by convection should occur within the reflective insulation. Such air currents would reduce or even eliminate the R-value of insulation just as air currents in walls, floors, or ceilings will increase heat transfer through those structure.
