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GAF DensDeck 1/4 in. Roof Board, 4 ft x 8 ft Gray Gypsum Cover Board
Regular price $29.50Orders start at $399 — combine any items to reach the minimum. Learn more
GAF DensDeck 1/4 in. Roof Board, 4 ft x 8 ft Gray Gypsum Cover Board
This is GAF DensDeck 1/4 in. roof board, a gray gypsum cover board supplied in 4 ft x 8 ft sheets and sold per sheet. It installs between insulation and the roof membrane to protect the insulation, improve membrane puncture resistance and create a uniform substrate. One sheet is one order unit.
Key Features:
- Gypsum cover board: DensDeck is a glass-mat gypsum roof cover board from GAF.
- Membrane protection: Installed under the membrane to shield insulation and improve puncture resistance.
- Uniform substrate: Provides a flat, consistent surface for adhered or mechanically attached membranes.
- 4 x 8 sheet: Each sheet covers 32 sq ft for quick area takeoffs.
- 1/4 in. thickness: The thinnest standard cover board thickness, suited where build-up height is limited.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | DensDeck |
| Sell unit | 1 sheet, 4 ft x 8 ft |
| Product line | GAF DensDeck Roof Board |
| Material | Gypsum |
| Color / finish | Gray |
| Thickness | 1/4 in. |
| Nominal size | 4 ft x 8 ft |
| Width | 4 ft |
| Length | 8 ft |
| Intended use | Roof cover board under low-slope membrane systems |
Coverage & How Much You Need:
One 4 ft x 8 ft sheet covers 32 sq ft of roof area. Divide the roof area by 32 and add allowance for waste and laps at joints to size your order.
Fit and Compatibility:
Use under approved low-slope membrane systems over polyiso or other approved insulation. Boards are fastened or adhered per the roofing system specification; fasteners, adhesive and membrane are sold separately.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One 4 ft x 8 ft sheet of 1/4 in. gray DensDeck gypsum roof board.
Q: How many sheets do I need?
A: Each sheet covers 32 sq ft; divide roof area by 32 and add 5 to 10 percent for waste and joints.
Q: Why add a cover board?
A: A cover board protects the insulation below the membrane, improving puncture resistance and giving the membrane a uniform surface.
Q: How is it attached?
A: Attachment method is not stated here; follow the roofing system manufacturer's approved fastening or adhering requirements.
Q: Are thicker DensDeck options available?
A: DensDeck roof board is offered in other thicknesses through related product lines, including 1/2 in. and 5/8 in. primed options.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
A 1/4 in. cover board is the go-to where overall assembly height is tight but a protective layer over polyiso is still required. Stagger joints between the cover board and the insulation below so seams do not stack, and leave a small gap at board joints per the system spec. Where heavy foot traffic or ballasted systems are involved, consider a thicker cover board.
Gypsum boards are heavy and edges are sharp; carry sheets with a partner and wear gloves, and keep board edges supported to avoid breakage.
Order GAF DensDeck 1/4 in. roof board by the 4 ft x 8 ft sheet for your membrane assembly.
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