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Toprock® DD Plus

ROCKWOOL Toprock® DD Plus is a high-density bitumen-coated insulation board for low-slope roof applications. It is compatible as the substrate for torched, hot mopped and self-adhered membrane systems.

20250512 RW-NA PROD 1689
20181109 RWNA PHO 526

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  • FM Approved
  • ULC Listed
  • Miami-Dade County Approved
  • UL Classified - CA/USA

Popular applications

  • Roof insulation
  • Low slope roof insulation

About this product

ROCKWOOL Toprock® DD Plus is a high-density, bitumen coated stone wool insulation board for low-slope roof applications. Toprock DD Plus is compatible as the substrate for torched, hot mopped, or self-adhered membrane systems.

Toprock DD Plus is noncombustible, will not develop toxic smoke or promote flame spread even when directly exposed to fire. Also offering improved sound absorbency and dimensional stability, Toprock DD Plus is designed to maintain performance for the long-term as part of your building envelope.

  • Noncombustible and fire resistant
  • NCC (Non Combustible Core) Rated Roof Insulation
  • Torched or hot mopped solutions
  • Water and moisture repellent
  • Dimensional stability to maintain performance
  • Excellent acoustic performance

Why use stone wool insulation

  • Stable long-term R-values for superior thermal performance.
  • Naturally fire resilient stone, will not develop toxic smoke or promote flame spread, even when exposed to a fire.
  • Stone wool provides excellent noise reduction and sound absorption to help you create quieter, more productive environments.
  • Water resistant, stone wool does not rot or promote the growth of mildew, fungi or mold.
  • Dual-density boards minimize damage from foot traffic and weather.
  • Dimensionally stable, stone wool does not expand or contract due to temperature variances.

Applications

  • Versatile insulation for low-slope roof applications.
  • Compatible with torched or hot mopped membrane systems.
  • SBS or modified bitumen membranes.
  • A component of fire-rated low slope roof assemblies.
  • Used in applications with very severe hail (VSH) conditions.

Product certificates

  • FM Approved
  • ULC Listed
  • Miami-Dade County Approved
  • UL Classified - CA/USA

Toprock® DD Plus sizes, dimensions & packaging

Find Toprock® DD Plus thickness, width, length and pack quantities—everything you need for accurate specification and ordering.

All
  • All
  • 7.6
  • 9.5
  • 11.4
  • 13.3
  • 15.2
  • 17.1
All
  • All
  • 2
  • 2.5
  • 3
  • 3.5
  • 4
  • 4.5

Specifications & testing

Explore Toprock® DD Plus specifications and test results, based on relevant industry standards.

NameValueUnitTest standard
NCC (Non Combustible Core) Rated Roof InsulationPassedFM 4470
Flame spread index0ASTM E84
Smoke Developed Index0ASTM E84
Combustibility of Materials at 750 °CNon-combustibleASTM E136
Determination of Non Combustibility of Building Materials Non-combustibleCAN/ULC S114
Fire Tests of Roof CoveringsClass ACAN/ULC S107-03
Heat Release Rate of Roofing Assemblies with Combustible ComponentsClass 1NFPA 276
Corrosion of Steel PassedASTM C665
R-Value / inch @ 75 °F3.8hr.ft².F/BtuASTM C518 (C177)
RSI value / 25.4 mm @ 24 °C0.67m²K/WASTM C518 (C177)

Toprock® DD Plus technical documents & resources

Download TToprock® DD Plus technical documents and resources, including the product data sheet, to support accurate specification and efficient project planning.

Toprock DD Plus flat roof insulation - Data sheet

Toprock DD Plus flat roof insulation - Data sheet

ROCKWOOL TOPROCK® DD Plus is a high-density, bitumen-coated stone wool insulation board for low-slope roof applications.

Toprock tapered, flute filler and cant strip components

Toprock tapered, flute filler and cant strip components

ROCKWOOL Toprock® fabricated stone wool insulation products are noncombustible – providing increased fire resistance, water resistant, and offer long-term dimensional stability.

Construction Details - Industrial Commercial Masonry Construction with Exterior Insulation up to 4 stories

Construction Details - Industrial Commercial Masonry Construction with Exterior Insulation up to 4 stories

Construction Details - Existing Multi Wythe Masonry Retrofit with Interior Insulation

Construction Details - Existing Multi Wythe Masonry Retrofit with Interior Insulation

Construction Details - Commercial Steel Frame Construction Heavyweight Cladding

Construction Details - Commercial Steel Frame Construction Heavyweight Cladding

Construction Details - Wood Frame Construction Heavyweight Cladding

Construction Details - Wood Frame Construction Heavyweight Cladding

Toprock DD Plus_072200 Roof and Deck Insulation GUIDESPEC EN_US

Toprock DD Plus_072200 Roof and Deck Insulation GUIDESPEC EN_US

Guidelines for cutting stone wool insulation

Guidelines for cutting stone wool insulation

Properly cutting stone wool insulation ensures fit and maintains performance, preventing safety and efficacy issues.

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Product support & insights

From expert technical guidance to real-world case studies and certified sustainability documents, access the tools and insights that support confident, high-performance building with stone wool insulation.

Speak to an expert

Contact our technical team for product, application, and building science support on stone wool insulation.

Technical
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View our case studies

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Charlie West Tower

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