M-BLOC® Type C Gypsum Board End Tape

M-BLOC® Type C Gypsum Board


M-Bloc® Type C interior gypsum panels treated with AzoTech™ fungicide were developed as an improved mold resistant wallboard, with additional properties to enhance the core of this type X wallboard to achieve superior performance when used in specific fire rated assemblies. M-Bloc® Type C interior gypsum panels consist of a fire and mold resistant core encased in 100% recycled paper. Additionally the core has been reinforced with fibers, increasing its strength and providing fire resistance ratings when used in tested assemblies.

At an independent laboratory, certified in accordance with ISO 17025-2005, M-Bloc panels have been tested to the industry’s most rigorous standards achieving the best results possible. Per ASTM G 21 the panels attained a 0 and ASTM D 3273 scored a perfect 10, thus minimizing the risk of mold and mildew growth.

Products manufactured by American Gypsum contain no asbestos. AzoTech™ is a trademark of a Syngenta Group Company.

Basic Uses

M-Bloc Type C interior gypsum panels are used as a covering material for interior walls and ceilings in residential and commercial applications that often require specific fire rated assemblies. It is designed for direct attachment by screws, nails or adhesive to wood or metal framing. M-Bloc Type C interior gypsum panels can be finished the same as regular gypsum wallboard and they accept a wide variety of attractive finishes.


M-Bloc Type C interior gypsum panels have attained the GREENGUARD Indoor Air Quality Certified® and the GREENGUARD Children & Schools Indoor Air Quality CertifiedSM status.

The GREENGUARD INDOOR AIR QUALITY CERTIFIED Mark is a registered certification mark used license through the GREENGUARD Environmental Institute.

Product Data


Thickness Widths Lengths Edge Type
1/2" (12.7mm) 4' (1219mm) 12' (3658mm) Tapered
5/8" (15.9mm) 4' (1219mm) 8'-12' (2438-3658mm) Tapered

Special lengths or edges may be available on special order. Consult your American Gypsum sales representative for details.

Technical Data

Storage & Handling

Gypsum 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. GYPSUM BOARD MUST BE KEPT DRY to prevent the growth of mold. Adequate ventilation shall be provided to prevent condensation.

Gypsum board that has visible mold growth must not be used. For additional information refer to Gypsum Association publication, “Guidelines for the Prevention of Mold Growth on Gypsum Wallboard” (GA-238).

Gypsum board must be stored in an area that protects it from adverse weather conditions, condensation, and other forms of moisture. Job site conditions that can expose gypsum board to water or moisture must be avoided.

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 must be delivered to the job site as near to the time it will be used as possible. Individuals delivering gypsum board to jobsites should ensure that it is carried, not dragged, to place of storage/installation to prevent damage to finished edges.

Applicable Standards

Mold Resistance Score of 0 (ASTM G 21)
Score of 10 (ASTM D 3273)
Manufacturing ASTM C 1396 section 5 (C 36)
Federal Specification - SS-L-30D Type III and Type VII, Grade X
Installation ASTM C 840
Gypsum Association GA-216
Gypsum Association GA-214
Surface Burning Characteristics ASTM E 84
Flame Spread 15
Smoke Developed 0

Fire Resistance Ratings

LEED / Green

LEED Contributions

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.