DEXcell® FA Glass Mat Roof Board

This mold- and moisture-resistant gypsum panel is a substrate board, thermal barrier and/or coverboard for commercial roofing applications.


3-Part Guide Specs



Submittal Builder

Recommended for fully adhered roof systems

Provides increased fire safety and acoustical enhancement

  • Coated facer improves adhesive bond.
  • Ideal coverboard or thermal barrier.

DEXcell® FA Glass Mat Roof Board has heavy-duty coated fiberglass facers and an enhanced mold-resistant gypsum core. This mold- and moisture-resistant gypsum panel is a substrate board, thermal barrier and/or coverboard for commercial roofing applications. It scores and cuts easily, and is specially coated on the front, back and sides for easy handling.

Use it for a wide variety of roofing systems, including fully adhered, mechanically attached and ballasted roofs using single-ply membranes, modified bitumen, fluid applied, built-up roofing, spray foam and metal.


  • Use DEXcell® FA Glass Mat Roof Board as a substrate board and for thermal protection in roofing assemblies. It provides increased fire safety and acoustical enhancement. It also serves as a substrate for a vapor retarder and/or continuous substrate for the application of roofing membranes. This board provides increased moisture and mold resistance.
  • Use it as an insulation coverboard in roofing assemblies. DEXcell FA Glass Mat Roof Board protects and supports the roof membrane; provides increased fire, moisture and mold resistance; and reduces the potential for penetration damage to the membrane.
  • Use it to sheathe the roof side of parapet and penthouse walls.


  • Scores and snaps easily.
  • Fiberglass mat on face and back has special coating for easy handling.
  • Meets ASTM C1177.
  • Meets FM Class 1 and UL Class A fire ratings for roofing systems up to unlimited slope per UL 790/ULC S107.
  • Approved component in specific UL fire-rated designs.
  • Use it as part of a class A, B or C roof covering that has been tested in accordance with UL 1256, ULC CAN-S126 or FM 4450. No additional thermal barrier is required as per IBC 2603.
  • Anti-microbial per ASTM D6329.
  • Resists the growth of mold per ASTM D3273 with a score of 10, the best possible score.
  • Eliminates the need for a field-applied primer for many fully adhered roofing membrane applications. Please see system manufacturers’ application recommendations.
  • High-density coverboard/thermal barrier.
  • 5/8 inch (15.9 mm) DEXcell® FA Glass Mat Roof Board is UL Classified for use in numerous hourly rated UL assemblies, including UL "P" roof assemblies; refer to UL Certifications Directory: Meets Type X per ASTM C1177.


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1/4", 1/2", 5/8"



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