DensDeck®

Prime Roof Board

Prime Roof Board

Why DensDeck® Prime Roof Boards?

The patented DensDeck® design employs glass mat facings front and back that are embedded into a water resistant and moisture resistant treated gypsum core, providing excellent fire resistance, moisture resistance, and wind uplift properties. The unique construction of DensDeck® Prime Roof Boards provides excellent flute spanning and will help stiffen and stabilize the roof deck. Additionally, DensDeck® Prime has been shown to withstand de-lamination, deterioration, warping, and jobsite damage more effectively than roofing membrane substrates such as paper-faced gypsum board, fiberboard, and perlite insulation.

Uses

Roof system manufacturers and designers have found DensDeck® Prime Roof Board to be compatible with many types of roofing systems, including:

  • Modified asphalt
  • Single ply
  • Metal systems
  • Re-cover board

 

It can also be used as an overlayment for polyisocyanurate and polystyrene insulation. DensDeck® Prime can also be used as a form board for poured gypsum concrete deck in roof applications as well as a substrate for spray foam roofing systems. 1/2" and 5/8" DensDeck® Prime may also be used in vertical applications as a backer board or liner for the roof side of parapet walls.

DensDeck® Prime allows the bonding of cold mastic modified bitumen and torching directly to the surface. Refer to specific membrane system application instructions. System manufacturers and designers have found DensDeck® Prime to be compatible with bonding adhesives for fully-adhered single-ply membrane applications and has been shown to extend the adhesive usage.

DensDeck® Prime Roof Board's exceptional moisture resistance and low R-value make it the preferred substrate for vapor retarders. An excellent fire barrier, it features a noncombustible core and inorganic surface that offers greater fire protection than other conventional commercial roofing products when applied over combustible roof decks and steel decks. DensDeck® Prime is FM tested and approved as the only 1/2' gypsum product to meet the calorimeter requirements for conventionally insulated decks. Tested in accordance with ASTM E84, its surface- burning characteristics are Flame Spread-0 and Smoke Developed-0. 5/8" DensDeck® Prime can replace any generic type X gypsum board in any roof assembly in the UL Fire Resistance Directory under the prefix “P.”

 

Manufacturer

G-P Gypsum Corporation

133 Peachtree Street, N.E.

Atlanta, GA 30303

Technical 1-800-225-6119 (8-7 ET) 

Available Sizes

Note:  Product sizes, dimensions, and widths are nominal values and are subject to normal manufacturing/packaging tolerance and variation.
  • R-Values
    0.28
  • Weights, nom. lbs. / sq. ft.
    1.2 (5.9)
  • Bending Radiuses
    4' (1,219 mm)
  • Permeance Perms
    >30 (>1,710)
  • Flute Spanabilities
    2.63" (66.8 mm)
  • R-Values
    0.56
  • Weights, nom. lbs. / sq. ft.
    2.0 (9.8)
  • Bending Radiuses
    6' (1,829 mm)
  • Permeance Perms
    >23 (>1,300)
  • Flute Spanabilities
    5” (127 mm)
  • R-Values
    0.67
  • Weights, nom. lbs. / sq. ft.
    2.5 (12.2)
  • Bending Radiuses
    8' (2,438 mm)
  • Permeance Perms
    >17 (>970)
  • Flute Spanabilities
    8" (203.2 mm)

Product Properties

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