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GAF DEXcell Glass Mat Roof Board 1/4 in. x 4 ft. x 8 ft. White Gypsum Cover Board
Regular price $28.25Orders start at $399 — combine any items to reach the minimum. Learn more
GAF DEXcell Glass Mat Roof Board 1/4 in. x 4 ft. x 8 ft. White Gypsum Cover Board
GAF DEXcell Glass Mat Roof Board is a 1/4 in. x 4 ft. x 8 ft. white gypsum panel with coated fiberglass facers for commercial roofing use. It serves as a substrate board, thermal barrier, and/or insulation cover board, sold per piece. It pairs with mechanically attached and ballasted single-ply membranes and metal roofing systems.
Key Features:
- Moisture resistant core: The gypsum core with coated fiberglass facers meets or exceeds ASTM C1177 for moisture resistance.
- Mold resistant: The board meets both ASTM G21 and ASTM D3273 for mold resistance.
- Fire protection: 1/4 in. DEXcell Glass Mat Roof Board can be used as a UL Class A thermal barrier as fire protection from below.
- Easy handling: Special coating on the front, back, and sides helps reduce fiber fly and irritation, and the board scores and cuts easily.
- Membrane protection: As a cover board it protects and supports the roof membrane against damage from roof traffic and hail or other impacts pursuant to FM 4470.
- Fire and sound benefit: Provides increased fire resistance pursuant to ANSI/UL 790 and increased protection from sound transmission versus systems with no cover board.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | GAF |
| Sell unit | 1 panel, 1/4 in. x 4 ft. x 8 ft. |
| Product line | DEXcell Glass Mat Roof Board |
| Available colors | White |
| Available sizes | 1/4 in. x 4 ft. x 8 ft. |
| Material | Glass mat faced gypsum board |
| Color / finish | White |
| Thickness | 1/4 in. |
| Dimensions | 4 ft. x 8 ft. panel |
| Approvals | Meets or exceeds ASTM C1177; ASTM G21 and ASTM D3273 mold resistance; UL Class A thermal barrier (1/4 in.); ANSI/UL 790; FM 4470 |
| Intended use | Substrate board, thermal barrier, and/or insulation cover board for commercial roofing; substrate for vapor retarders and membrane application |
| Assembly | Scores and cuts easily |
Coverage & How Much You Need:
One piece is a 4 ft. x 8 ft. panel, covering 32 sq ft of roof deck. Divide total roof area by 32 and add waste allowance to size the job.
Fit and Compatibility:
Use with mechanically attached and ballasted single-ply membranes and metal roofing systems, and as a substrate for vapor retarders or membrane application. Membrane and fastening systems are sold separately.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One 1/4 in. x 4 ft. x 8 ft. DEXcell Glass Mat Roof Board panel.
Q: Can it serve as a thermal barrier?
A: Yes, the 1/4 in. board can be used as a UL Class A thermal barrier as fire protection from below.
Q: Which roofing systems does it work with?
A: It is designed for a wide variety of systems, including mechanically attached and ballasted single-ply membranes and metal roofing.
Q: Is it mold resistant?
A: Yes, it meets both ASTM G21 and ASTM D3273 for mold resistance, and the core meets or exceeds ASTM C1177 for moisture resistance.
Q: How easy is it to cut?
A: The panel scores and cuts easily, and coated faces and edges help reduce fiber fly and irritation during handling.
Q: Does it help with hail damage?
A: As an insulation cover board it protects and supports the membrane to help prevent damage from roof traffic and hail or other impacts pursuant to FM 4470.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Choose the 1/4 in. thickness when a UL Class A thermal barrier from below or a slim cover board over polyiso is specified. Stagger board joints from insulation joints, fasten per the membrane manufacturer's layout, and cut with a utility knife and straightedge. Keep edges coated and dry-stored to preserve the ASTM C1177 moisture performance.
Wear gloves, eye protection, and a dust mask when cutting gypsum board, as scoring and snapping produces sharp edges and dust.
Order GAF DEXcell Glass Mat Roof Board today to add moisture- and mold-resistant cover board protection to your commercial roof assembly.
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