What is Foil Insulation R-Value?
Insulation is measured in R-values. This is also used to describe the insulating product's resistance to transfer heat and how the product will perform as a heat insulator or absorb it. The higher R-value ensures better insulation of heat flowing in or out of the home. When referring to reflective foil insulation, the R-value measurement relates to the total heat resistance ability of the roof or wall after the insulation is installed. Radiant heat is often overlooked because r-value does not account for radiant heat. Radiant heat transfers up to 75% of its total heat gain or loss to the buildings. Reflective foil insulation blocks 97% of the radiant heat transfer and forms a thermal break or vapor barrier, from the place it is installed. Simply stated, the foil radiant barrier reflects heat. By doing this, it makes the R-value of material more effective. Radiant barrier foil by itself does not provide any R-value; the product along with which the reflective foil is decked has its R-value. When Radiant Barrier is attached to some products of foam Insulation, the product will then have R-value of the foam, sheathing or OSB decking, but the Reflective Foil does not actually provide any additional R-Value. Foam Insulation has some R-value. If you have airflow around the object, R-Value does not matter. For instance, if you wear a jacket and allow the air to get between you and the jacket it will not matter how thick the jacket is because you have no air space. So unless you completely air-seal the bubble foil you will not get the full effectiveness of the R-value R-value measures the insulation resistance to conductive heat, which is heat by physical contact. This is important when you are filling up a wall cavity with bulk insulation, and there's contact between the interior drywall and the exterior sheathing. The R-value changes because of the type of heat you use and where you live. It also changes between new and existing homes.