CertainTeed Sheathing Treated Core is a water-repellent Type X gypsum sheathing for application to the outside of building framing members, and serves as the base for the exterior wall finish. It can be used as attachments to the outside of exterior wall framing as a water-resistant underlayment for various siding materials and also in fire resistance rated designs.

Technical Information

Product Data:

  • Thickness: 5/8" (15.9 mm) Type X
  • Lengths: 8' standard
  • Width: 4' (1220 mm) standard
  • Edges: Square Paper: 100% recycled water repellent face and backing paper
  • Weight: 5/8" (15.9 mm): 2.3 lb/ft2 (11.2 kg/m2)
  • Packaging: Two pieces per bundle; face-to-face and end-taped. Special widths, lengths or edges may be available on special order. Consult your CertainTeed sales representative.
  • Applicable Standards: meets ASTM C1396, Type X standards ASTM C79
  • Surface Burning Characteristics: CertainTeed Sheathing Treated Core Type X Gypsum Board has a Flame Spread rating of 15 and Smoke Developed rating of 0, in accordance with ASTM E 84, (UL 723, UBC 8-1, NFPA 255, CAN/ULC-S102). "UL Classified for Fire Resistance (ANSI/UL 263; ASTM E119) and listed under UL File No. CKNX.R3660" Consult the GA-600 Fire Resistance Design Manual or UL Fire Resistance Directory, Volume 1 for specific information regarding the construction of fire resistance rated assemblies.

For complete Technical Data, please see the Product Data and Submittal Sheet. See important Fire Safety Information.


CertainTeed Regular Gypsum Board accepts most types of paints, textures and wall covering materials. The surface shall be primed and sealed with a full-bodied latex primer before applying a final decorative material. This will equalize the suction between the joint compounds and the paper surface. For best painting results, all surfaces, including joint compound, should be clean, dust-free and not glossy. If glossy paints are used, a thin skim coat of compound over the entire surface, Level 5 finish, is recommended to reduce highlighting or joint photographing. This method is also recommended for areas of critical side lighting of natural or artificial light sources. A sealer application under wallpaper or other wall coverings is also recommended so 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. Applicable Standards and References ASTM C840 ASTM C1280 GA-216 GA-253 Consult the GA-600 Fire Resistance Design Manual or UL Fire Resistance Directory, Volume 1 for specific information regarding the construction of fire resistance rated assemblies. For complete installation instructions, please see ProRoc Install Like the Pros, Gypsum Board Installation Guide.

Warranty Details

Please see the attached document for complete warranty details.

Sustainability Information

CertainTeed takes pride in providing the best solutions to make the spaces where we work, live, and play healthier and safer. This means offering high-performing products that create better living environments.

Our products improve building energy efficiency and reduce building energy consumption for the life of the structure. As a result, they help conserve nonrenewable energy sources, decrease dependence on hydrocarbons and lower greenhouse gas emissions.

CertainTeed’s ongoing commitment to sustainability in our manufacturing operations incorporates the principles of industrial ecology, managing energy and water, and reducing waste.


Our ecomedes Sustainable Product Platform allows you to quickly access the product information and certifications you need, calculate contributions to LEED and other green building rating systems and create and save a group of products using the project feature. The information is free to access and always up to date.

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