JM Releases Full Line of Densities for JM CladStone™ Water & Fire Block Mineral Wool Insulation

Johns Manville (JM), a Berkshire Hathaway company and leading building products manufacturer announced the launch of JM CladStone™ 110 and JM CladStone™ 80. With this release, JM now offers a full line of product densities on its exterior commercial mineral wool insulation, JM CladStone™ Water & Fire Block. The insulation is offered in densities ranging from 4.5 pcf to 11.0 pcf, making it ideal for use in a variety of exterior cavity wall, rainscreen, and continuous insulation applications.

Johns Manville’s Commercial Mineral Wool Product Manager Eric Dake explained that the varying densities of JM CladStone™ are a crucial component for many installers. “JM CladStone™ mineral wool is a great material for insulating commercial buildings,” Dake said.

“Given the array of installation applications, from the exterior cavity wall to continuous insulation, installers need insulation in a variety of densities so that it can meet the unique demands of the application and installation. With JM CladStone™, installers can choose from four different densities, 4.5 pcf, 6.0 pcf, 8.0 pcf, or 11.0 pcf, that work with a variety of exterior cladding systems,” he said.

The latest release of JM CladStone™ 80 (8.0 pcf) and JM CladStone™ 110 (11.0 pcf) rounds out the JM CladStone™ portfolio, offering a variety of densities for diverse and varied applications and installations. Each of the insulations in the CladStone™ portfolio is ideal for continuous insulation applications and exterior wall assemblies. As part of a continuous insulation assembly, CladStone™ helps improve a building’s energy efficiency and temperature control by decreasing or preventing thermal bridging. This can be a key component to meeting many of the newer energy code requirements for building insulation.

JM CladStone™ is non-combustible, making it an exceptional solution for fire-resistant applications. Additionally, JM CladStone™ is water-resistant and allows for effective water drainage from an exterior cavity wall assembly.

As codes evolve to incorporate more and more stringent requirements for insulating materials, insulations like JM CladStone™ that offer thermal control, acoustical performance, fire-resistance, and water-resistance will prove to be robust solutions for ever more challenging applications. JM CladStone™ Water & Fire Block is available to customers in the United States and Canada. For more information about the JM CladStone™ Insulation portfolio, visit

About Johns Manville

Johns Manville, a Berkshire Hathaway company (NYSE: BRK.A, BRK.B), is a leading manufacturer and marketer of premium-quality products for building insulation, mechanical insulation, commercial roofing and roof insulation, as well as fibers and nonwovens for commercial, industrial and residential applications. JM serves markets that include aerospace, automotive and transportation, air handling, appliance, HVAC, pipe and equipment, filtration, waterproofing, building, flooring, interiors and wind energy. In business since 1858, the Denver-based company has annual sales over $3 billion and holds leadership positions in all of the key markets that it serves. Johns Manville employs 8,000 people and operates 42 manufacturing facilities in North America, Europe and China. Additional information can be found at

Eric Dake