Exterior Gypsum Sheathing
Exterior Gypsum Sheathing is a water-resistant product designed for attachment to exterior side-wall framing as an underlayment for various exterior siding materials such as wood, metal or vinyl siding, masonry veneer, stucco, shingles, etc. The panel is manufactured with a wax-treated, water-resistant core faced with water-repellent paper on both face and back surfaces and long edges.
Exterior Gypsum Sheathing is available in 1/2" & 5/8" thick, 4' wide square edge product. 5/8" Exterior Gypsum Sheathing has a Type X core, for use in fire rated assemblies.
Gypsum wallboard manufactured by American Gypsum contains no asbestos
Exterior Gypsum Sheathing is recommended for use in residential or commercial buildings, and provides fire resistance and additional structural strength when used under exterior finishes such as wood, metal or vinyl siding, masonry veneer, stucco, shingles, etc. Exterior Gypsum Sheathing is designed for direct attachment to wood framing with galvanized nails or staples and screws, or metal framing by the use of screws. The joints are not intended for finishing with drywall joint compound and tape.
|1/2" (12.7mm)||4' (1219mm)||8' - 12' (2438mm - 3658mm)||Square Edge|
|5/8" (15.9mm)||4' (1219mm)||8' - 12' (2438mm - 3658mm)||Square Edge|
Special lengths may be available on special order. Consult your American Gypsum sales representative for details.
Storage and Handling
Exterior Gypsum Sheathing board does not generate or support the growth of mold when it is properly transported, stored, handled, installed, and maintained. However, mold spores are present everywhere and when conditions are favorable; mold can grow on practically any surface.
Where necessary, Exterior Gypsum Sheathing may be stored outside for up to one month, but must be stored off the ground and shall be sheltered from the elements with a protective covering. Sufficient risers must be used to assure support for the entire length of the wallboard to prevent sagging.
Gypsum board must be protected during transit with a weather-tight cover in good condition. Plastic shipping bags are intended to provide protection during transit only and must be promptly removed upon arrival of the load. Failure to remove the shipping bag can increase the likelihood of developing conditions favorable to the growth of mold.
Gypsum board that has visible mold growth must not be used. For additional information, refer to Gypsum Association publication,
Gypsum board shall always be stacked flat - NEVER on edge or end. Gypsum board stacked on edge or end is unstable and presents a serious hazard should it accidentally topple. Gypsum board should be placed so weight is evenly distributed and the floor is not overloaded.
ASTM C 1396 section 9 (C 79)
Federal Specification SS-L-30D Type II (1/2")
Federal Specification SS-L-30D Type II Grade X (5/8")
ASTM C 1280
Gypsum Association GA-253
Gypsum Association GA-254
|Surface Burning Characteristics||
ASTM E 84
Flame Spread 0
Smoke Developed 0
Fire Resistance Ratings
Our products can contribute to the following credits within the Materials and Resources (MR) category.
- LEED MR Credit 2: Construction Waste Management
- LEED MR Credit 4: Recycled Content
- LEED MR Credit 5: Regional Materials
Our products can contribute to the following credit within the Indoor Environmental Quality (IEQ) category.
- LEED IEQ Credit 4.6: Low-Emitting Materials - Ceiling and Wall Systems (SCHOOLS ONLY)
To learn more please click the LEED link at right.