Thermal Insulation and Fireproofing Materials

Thermal insulation and fireproofing materials reduce the flow of heat through the thickness of the material. They are typically fiber-based or foam structures prepared from thermally-stable materials. There are four basic material types of thermal insulation and fireproofing materials: fiberglass, glass wood, polymeric materials, cellulose fibers, and ceramics or refractories. Fiberglass is offered typically as batting or as a high-loft, flexible structure; however, board-like products are also suitable for many industrial applications. Glass wool is spun from slag, rock, glasses or minerals that have been melted and produced as fibers. Polymeric materials have high molecular weight materials and are often hydrocarbon based. They can be prepared into films, fibers, fabrics or foams. Cellulosic fibers are prepared from wood pulp, cotton and other natural resources. Refractories are hard, heat-resistant thermal insulation and fireproofing materials such as alumina cement, fire clay, bricks, pre-cast shapes, cement or monolithics and ceramic kiln furniture. Ceramics and refractories have high melting points are suitable for applications requiring wear resistance, high temperature strength, electrical or thermal insulation or other specialized characteristics.

There are five main forms for thermal insulation and fireproofing materials: bulk chopped fibers, textiles or fibrous mats, foam, board and block insulation, and films or foils. Bulk chopped fibers provide loose, flowable insulation that can be filled or applied into an application, or serve as the basis for a textile or mat. Textiles and fibrous mats are made by weaving, knitting, braiding or web extrusion. These thermal insulation and fireproofing materials can also be needlepunched, formed from a slurry (wet laid), or produced in other ways. The properties of finished products depend upon the manufacturing process, fiber material and fiber size. Foam insulation materials are made from low-density elastomers, plastics, and other materials with various porosities. They are used in a variety of architectural, industrial, medical, and consumer applications. Board and block insulation is made from a variety of base materials in the form of a sheet, strip, plate or slap. Thermal insulation and fireproofing materials are also prepared from films, foils or composite structures with foam, fabrics or other materials.

Thermal insulation and fireproofing materials differ in terms of specifications and features. Use temperature and thermal conductivity are two important parameters to consider. Use temperature is the range through which a material can be exposed without degradation of its structural or other required end-use properties. Thermal conductivity is the linear heat transfer per unit area through a material for a given applied temperature gradient. In terms of features, some thermal insulation and fireproofing materials are flame-retardant, electrically insulating, and chemical or fuel resistant. Others are UL approved, a designation from Underwriters Laboratories (UL). Hydrophilic (absorbent) and hydrophobic (waterproof) thermal insulation and fireproofing materials are also commonly available.