Cavityrock®
ROCKWOOL Cavityrock® is a stone wool insulation board designed for exterior cavity wall and rainscreen applications. It is compatible with numerous cladding attachment systems, including z-girts, clip-and-rail systems and masonry ties.
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Popular applications
- Exterior wall insulation
- Roof insulation
- Rainscreen insulation
- Cavity wall insulation
- Metal roof insulation
About this product
ROCKWOOL Cavityrock® is a stone wool insulation board designed for continuous insulation in exterior cavity wall and rainscreen applications. Cavityrock is a durable, noncombustible solution that is approved for use in many NFPA 285-compliant designs.
Cavityrock offers reliable thermal performance, improved acoustic comfort, and moisture resistance to maintain long term performance. Also available in a black mat finish, Cavityrock Black reducing installation time in open-joint cladding systems.
- Noncombustible and fire resistant
- Component of NFPA 285 assemblies
- Water and moisture repellent
- Made from natural and recycled materials
- Inorganic, does not promote mold growth
- Dimensionally stable to maintain performance
Why use stone wool insulation
- Noncombustible and fire resistant, stone wool works to contain a fire and prevent its spread.
- Water resistant and vapor permeable for effective drainage from an exterior wall assembly.
- Durable inorganic material that does not rot or promote the growth of mildew, fungi or bacteria
- Cavityrock Black is available with a black mat finish for improved open-joint cladding system aesthetics.
Applications
- Designed as exterior continuous insulation for above-grade wall applications.
- Ideal for exterior cavity walls, rainscreens, and open-joint cladding systems.
- Suitable for commercial and industrial buildings.
- Fits seamlessly with pre-engineered cladding attachment systems like clip and rails, continuous girts, and masonry ties.
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Cavityrock® sizes, dimensions & packaging
Find Cavityrock® thickness, width, length and pack quantities—everything you need for accurate specification and ordering.
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- 33.6
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Specifications & testing
Explore Cavityrock® specifications and test results, based on relevant industry standards.
Name | Value | Unit | Test standard |
---|---|---|---|
Mineral Fiber Block and Board Thermal Insulation | Type IVB Compliant | ASTM C612 | |
Mineral Fiber Thermal Insulation for Buildings | Type 1 Compliant | CAN/ULC S702 | |
Flame spread index | 0 | ASTM E84 | |
Smoke Developed Index | 0 | ASTM E84 | |
Combustibility of Materials at 750 °C | Non-combustible | ASTM E136 | |
Determination of Non Combustibility of Building Materials | Non-combustible | CAN/ULC S114 | |
Corrosion of Steel | Passed | ASTM C665 | |
Density Description | 6.2 lbs/ft³ (100 kg/m³) outer layer and 3.8 lbs/ft³ (61 kg/m³) inner layer | ||
R-Value / inch @ 75 °F | 4.2 | hr.ft².F/Btu | ASTM C518 (C177) |
RSI value / 25.4 mm @ 24 °C | 0.74 | m²K/W | ASTM C518 (C177) |
Determination of Fungi Resistance | Passed | ASTM C1338 |
Cavityrock® technical documents & resources
Download Cavityrock® technical documents and resources, including the product data sheet, to support accurate specification and efficient project planning.

Cavityrock cavity wall and rainscreen insulation - data sheet

Cavityrock black features and benefits

Cavityrock - Commercial new construction builder’s guide

Additional information about ROCKWOOL cavityrock black

Construction Details - Commercial Steel Frame Construction Heavyweight Cladding

Construction Details - Existing Multi Wythe Masonry Retrofit with Interior Insulation

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

Cladding attachment solutions for exterior insulated commercial walls

Bending stone wool insulation for curved designs

Guidelines for cutting stone wool insulation
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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.