Cabot Light Gypsum Board has a core of noncombustible; dimensionally stable gypsum rock sandwiched between a face layer of 100% recycled ivory colored paper and a brown-back paper. The face paper is formed along each edge, wrapped around and sealed to the brown paper on the back side. This produces a strong yet flexible panel in convenient width and lengths to meet most commercial/residential construction requirements for wall and ceiling substrates. Even though Cabot Light Gypsum Board is a limited-combustible product with a Class A Flame Spread Rating it is not used in an assembly requiring a fire rating.
Cabot Light is a specialty gypsum board formulated to be up to 25% lighter than Cabot Regular Gypsum Board. The result is a superior board that is lighter in weight, sag resistant and easier to handle.
Cabot Light Gypsum Board can be used for most walls, partitions and ceilings in commercial and residential construction both new and renovations where framing members can be spaced up to 24" o.c. Since it can be installed on both walls and ceilings, it eliminates the need for two different board types on the job. Cabot Light Gypsum Board is an excellent barrier to the transmission of noise and thermal energies but must be installed in the proper thickness and method that has been tested to achieve the desired rating per Standard Specification for Application and Finishing of Gypsum Board, ASTM C 840, for non rated construction.
Cabot Light Gypsum Board is manufactured to meet or exceed the requirements of ASTM C 1396 Section 5 (Gypsum Wallboard) and Section 12 (Gypsum Ceiling Board) and CAN/CSA A82.27 and Installation Standards ASTM C840.
1. Exposure to excessive or continuous moisture and extreme temperature 52o C (125o F) should be avoided.
2. Store indoors and off ground surface.
3. Boards should be stacked flat with care taken to prevent sagging or damage to edges, ends and surfaces.
4. Storing board lengthwise leaning against framing is not recommended.
5. This board is nonstructural and should not be used as a nailing base to support heavy wall-mounted objects.
6. Maximum insulation load: 1.3 psf with 24" o.c. framing and 2.2 psf with 16" o.c. framing.
7. Maximum framing spacing on walls and ceilings is 24" o.c. and must be installed perpendicular to framing.
Surface Burning Characteristics: Flame Spread Rating of 15, Smoke Developed 0 per ASTM E 84 or CAN/UL-S102.
Thickness: 1/2" (12.7 mm)
Width: 4' (1220 mm)
Lengths: 8' (2440 mm) to 12' (3660 mm)
Edges: Tapered, Square
Packaging: Two pieces per bundle, face-to-face and end taped. Special lengths may be available, consult nearest Cabot Gypsum sales office.
Cabot Light Gypsum Board can be applied to wood framing with drywall nails or Type W screws and with special adhesives in combination with supplemental fasteners. Cabot Light may also be applied to light gauge metal framing with self-tapping Type S screws. See Tables I and II for framing and fastener spacing details. In general, apply gypsum board to the ceiling first at right angles to the framing. A horizontal application is also recommended for walls and partitions. This gives a stronger wall and reduces the number of joints to be finished. Start with the upper panels and cut opening for doors or windows from full panels or plan joints to occur on studs nearest the center of the openings. Use appropriate metal or plastic trim accessories on all exposed edges, corners and abutments.
Cabot Light Gypsum Board is designed to accept most types of paints, texture and wall covering materials. The surface should be primed and sealed with a full bodied quality latex primer before applying a decorative material. This will equalize the suction variation between the join compounds and the paper surface. If glossy paints are used in areas such as kitchens or bathrooms, a thin skim coat of compound over the entire surface is recommended to reduce highlighting or joint photographing. This method is also recommended in areas of severe side lighting of either natural or artificial light sources. A sealer application under wallpaper or other wall covering is also recommended so that the board surface will not be damaged if the covering is subsequently removed during redecorating. Joint treatment must be thoroughly dry before proceeding with primer-sealer application and final decoration.