rFOIL® Between-Joist reflective insulation consists of a double layer of polyethylene bubbles sandwiched between two highly reflective surfaces.This product has been specifically designed for insulating residential wall and ceiling assemblies; tabbed edges help to ensure the product is installed quickly and correctly, every time. Adding rFOIL® reflective insulation to your construction project improves the insulation value of the building envelope and significantly increases it's energy efficiency. As well, all products in this line are classified as Class 1/Class A in accordance with the ASTM-E84-09 fire test standard. The product was mounted in accordance to ASTM-E2599-08.