Which fiberglass form is commonly supplied as blanket-like material used to insulate large cavities?

• A. Board
• B. Wrap
• C. Pre form
• D. Batt insulation

Answer: (D)

Batt insulation refers to a flexible fiberglass blanket that comes as batts or rolls and is used to insulate large cavities. This blanket form is ideal because it can be unrolled or cut to fit between studs, joists, and in attic or floor cavities, filling wide spaces with fewer seams. Its flexibility lets you contour around irregular edges and obstacles, providing a continuous insulating layer when installed properly. Standard widths fit common framing spacings, and you can layer to reach the desired thickness and R-value. While other fiberglass forms exist—rigid boards for solid assemblies, wraps as protective coverings, and preforms for corners—the blanket-like batt form is best suited to large, open cavities due to its ease of fitting and ability to cover large areas efficiently.