Common Types of Insulation

Loose fill. Fiberglass is the most common loose fill material. It is preferred by insulation contractors for attics, because it can be blown in. A special truck with a strong blower is parked in the driveway. An approximately four-inch diameter hose is run from the truck-mounted blower to the attic, usually by way of an upstairs window located near the pull-down attic steps. One technician unloads bags of insulation into the blower hopper in the truck, while the other technician spreads or sprays the loose insulation around the attic, creating a blanket.

One advantage of loose fill is that it is easily installed around pipes and other attic obstacles as well as on top of existing insulation. Also, the blower simplifies the installation process by carrying the insulation from truck to attic. Loose fill may also be used to insulate empty wall cavities. One drawback of loose fill is that it can only be used in areas where it is completely contained or where gravity holds it in place. For example, it cannot be used to insulate crawl space or basement ceilings.

Blankets. Fiberglass blankets are usually precut into either rolls or batts. Batts are sheets specifically sized to fit between wall studs. They are typically used during the building process to insulate walls before sheetrock is hung. Fiberglass rolls are commonly used to insulate basement or crawl space ceilings. Because little equipment is required to install fiberglass batts and rolls, many do-it-yourselfers prefer them. One issue with installing fiberglass rolls or batts over existing insulation in the attic is that keeping the individual blankets parallel, so that there are no gaps between them, is often challenging.

Radiant barrier or reflective insulation. Radiant barriers are foils or films engineered to reflect radiant heat back in the direction from which it came. Radiant barriers can be installed in a number of areas in the home and are commonly installed in the attic. The radiant barrier is typically stapled to the underside of the roof rafters.