Fiberglass batts and blankets are the most common and widely available American insulation products. Batts and Blankets are composed of glass fibers, held together by an adhesive binder.
Loose-fill insulation is sold in densely packed bags. It is broken up and fed into a blowing machine to fill attics or closed cavities such as walls or vaulted ceiling. Loose-fill comes in two common varieties: fiberglass and cellulose.
Fiberglass and cellulose blowing wool can be sprayed directly onto vertical surfaces through a system referred to as wet spray. This material must be blown into open cavities, and is usually used in new construction or major remodel projects.
Plastic foam panels, such as expanded and extruded polystyrene, are available in four-by-eight or ten-by-eight-foot sheets of various thicknesses. Plastic foam panels create an air barrier, unlike fibrous insulation. If you seal the panels at their seams your are creating a continuous air barrier on the home's exterior.
Sprayed foam insulation comes in several different forms. It is among the most expensive of insulation materials, but often worth its higher price when adhesion, moisture resistance, air-sealing ability, and structural strength are important. It is used for walls, foundations, and roofs, and is usually applied by professional crews with truck-mounted equipment.