To maintain comfort, the heat lost in the winter must be replaced by your heating system and the heat gained in the summer must be removed by your cooling system. Properly insulating your home will decrease this heat flow by providing an effective resistance to the flow of heat.
Radiant barriers (Spray, reflective foil, reflective metal roof shingles, reflective laminated roof sheathing, and even reflective chips) are installed in homes-usually in attics-primarily to reduce summer heat gain, which helps lower cooling cost.
The barriers consist of highly reflective materials that reflects (or more specifically, re-mits) heat rather than absorbing it. They don't reduce heat conduction like thermal insulation materials.
Radiant barriers are move effective in hot climates than in cool climates, especially when cooling air ducts are located in the attic. Most radiant barrier products generally corresponds to a reflectivity up to 93%.
For energy efficiency, your home should be properly insulated from the roof down to its foundation. This includes the following areas:
Attic spaces, Attic access doors to unfinished attics,Knee walls in finished attics,