Closed Cell is a two-component, medium-density, one-to-one-by-volume spray-applied polyurethane foam. To produce Closed Cell, requires the use of an “A” component (ISO) and a blended “B” component (RESIN), which contains ZERO ozone-depleting blowing agents, catalysts, polyols, and fire-retarding materials. Closed Cell is an insulation system designed for use in residential applications. Use it in lieu of more traditional forms of insulating materials such as fiberglass, cellulose, or other loose-fill products. Typical areas where spray polyurethane foam is applied are exterior walls, vented attics, unvented attic assemblies, between floors, foundations, crawl spaces, HVAC ducts, fluid tanks, and cold storage units.