Mineral Fiber Batt Insulation
This information reflects our best understanding of product composition in 2015.
Mineral fibers are manufactured by spinning a molten mixture of rock wool (derived from igneous rocks such as basalt) and slag wool (derived from blast furnace slag from the steel industry) into fine fibers. An atomized binder (commonly urea...
Mineral fibers are manufactured by spinning a molten mixture of rock wool (derived from igneous rocks such as basalt) and slag wool (derived from blast furnace slag from the steel industry) into fine fibers. An atomized binder (commonly urea phenol-formaldehyde) is sprayed onto the fibers as they settle onto a conveyor belt in layers to form an insulation batt. When the batt has reached the desired thickness, it is conveyed into an oven to cure. A vapor barrier can be applied to the mineral fiber batt with an adhesive; however, this was found on only one of the mineral fiber batts in this survey and is not included in this profile. Mineral fiber batt insulation is a thermal insulation product that has high heat resistance, inherent resistance to fungal, mold, and mildew growth, and is water-repellant. It has a high insulating value and also acts as a good acoustical barrier. Because of its high heat resistance, it is sometimes used as a passive fire barrier. Mineral fiber batts are installed by cutting the batt to fit the wall cavity. Friction then holds the batt in place until drywall is installed.