The TaperedPlus DENSDeck System is a robust coverboard layer with high compressive strength for use in a warm flat roof waterproofing system.

DensDeck® Prime Roof Board is a robust cover board layer with high compressive strength for use in warm flat roof waterproofing systems. It is lightweight, easy to cut and install, providing enhanced durability and point load resistance to the waterproofing build up while also serving as a thermal and fire barrier to a roof and its parapets.

DensDeck® Prime Roof Board has glass mat facings that are embedded into a water / moisture resistant treated gypsum core with a pre-primed surface, aiding waterproofing membrane adhesion. The unique composition offers excellent fire resistance, moisture
resistance, and wind uplift properties.

The product is compatible with a wide range of waterproofing membranes and offers designers and specifiers a non combustible layer for spreading load above insulation products (see ROCKDeck section).

Key Benefits

Key benefits
• Non-combustible
• High compressive strength
• Mould Resistance
• Easy handling
• Easy cutting
• Withstands delamination, deterioration, warping


Mould Resistance
Rated maximum “10” for mould resistance on ASTM D3273
Fire Performance
Factory Mutual (FM) approvals
UL Certified
EN 13501-1, Class A1
Compressive strength
Tested in accordance with ASTM C473, 900 psi (nominal) was achieved
For information on performance in conjunction with insulation layers please refer to the ROCKDeck Section.

For fully adhered, partially adhered, and mechanically fastened
The DensDeck Prime Roof Board should be neatly fitted to all roof
penetrations and projections.
No more boards should be installed than can be covered with
membrane and completed before the end of each working or before
the onset of rainfall.
DensDeck® Prime Roof Board can be applied over insulation boards
and over existing roof surfaces.

Store Level and Keep Dry. Dewpoint or other conditions causing the presence of moisture can damage the product during
storage. Store away from incompatible materials such as acidic components.

Related Case Studies

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