Copyright Goodheart-Willcox Co., Inc. 126 Section 3 Specifications and Materials of application and amount of material. A high R-value number means good insulation qualities. Insulation materials are classified as: • Flexible (blanket or batt). • Loose-fill. • Reflective. • Rigid (structural and nonstructural). Flexible insulation is available in blanket and batt form. Blankets come in widths suitable to fit 16″ and 24″ ″ stud and joist spacing and in thicknesses from 1″ to 14″. ″ The body of the blanket is made of mineral or vegetable fiber, such as rock wool, glass wool, wood fiber, or cotton. Organic materials are treated to resist fire, decay, insects, and vermin. Blankets are covered with a paper sheet on one or both sides. The vapor barrier is installed facing the warm side of the wall. Batt insulation is made of the same material as blankets, in thicknesses from 3 1/2″ to 14″ ″ and lengths of 48″, ″ 93″, ″ and 96″. ″ Loose-fill insulation, Figure 7-26, is available in bags 6 or bales. It is either poured, blown, or packed in place by hand. Loose-fill insulation is made from materials such as rock wool, glass wool, and cellulose. This type of insulation is suited for insulating sidewalls and attics of buildings. It is also used to fill cells in block walls. Reflective insulation is designed to reflect radiant heat. It is made of a material surfaced with metal foil (usually aluminum foil). To be effective, the reflective surface must face an air space of at least 3/4″. When the ″ reflective surface contacts another material, such as a wall or ceiling, the reflective properties are lost along with the insulating value. This material is often used on the back of gypsum lath and blanket insulation. Rigid insulation is made of a foam material in sheet form. Common types are expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), and polyiso- cyanurate foam (PIR). These produce a lightweight, Glass Block Glass block is made by fusing two sections of glass together. A partial vacuum is created between the pieces, providing good insulating qualities. Edges are left rough to improve the bond with the mortar. Glass block is used in nonbearing applications, such as interior walls, screens, curtain walls, and windows. See Figure 7-25. Blocks are manufactured in three nominal sizes: 6″ × 6″, 8″ ″ × 8″, and 12″ ″ × 12″. Special blocks are ″ available for forming corners and curved panels. Plastics Plastics have many uses in construction. Plastic laminates attached to plywood serve as countertops, door veneer, and wall surfacing. Panels of wood or gypsum are printed, textured, and given a plastic vinyl coating. Plastic rain gutters and downspouts collect and distribute storm water. Plastic pipes are used for water-transmission, sprinkling, drainage, and sewage systems. Plastics are also used for many trim and ornamental items, such as moldings on doors and simulated wood carvings. Plastic materials are usually noted on the drawing and detailed in the specifications. Insulation The purpose of thermal insulation is to reduce heat transmission through walls, ceilings, and floors. When the outdoor temperature is warm, insulation keeps the heat from entering the structure. When the outdoor temperature is cool, insulation helps keep the warm air indoors. Insulation is manufactured in a variety of forms and types to meet specific construction requirements. Each type of material or composite system will have an R-value (resistance to heat transfer), depending on the manner Artazum/Shutterstock.com Figure 7-25. Glass block has many applications in construction. The shower enclosure in this home is constructed to form a radial wall section. Enclosures of this type can be constructed from prefabricated sections or individual block units. CertainTeed Corporation Figure 7-26. Loose-fill insulation is commonly used for insulating open attic areas. This insulation is designed to be installed with special pneumatic equipment. R-values ranging from R-11 to R-60 are achieved based on minimum installed thicknesses specified by the manufacturer.