Johns Manville Announces New VVSD Spiracoustic Plus Duct Liner for 6-8” Ducts

Johns Manville (JM), a Berkshire Hathaway company and leading building products manufacturer, announced the release of VVSD (very, very small diameter) Spiracoustic Plus® spiral duct liner. This product is the first of its kind, engineered specifically for smaller diameter spiral duct applications, with outer diameters ranging from 6 to 8 inches. The insulation is offered in 1-inch thickness only and is the newest addition to the Spiracoustic Plus portfolio.

Based on JM’s proprietary fiberglass board technology, Spiracoustic Plus duct liner has factory-made, evenly spaced kerfs to allow the material to conform to the inside diameter of spiral ducts. This creates a single-wall insulation solution for spiral duct applications of all sizes.

Brennan Hall, JM’s Senior HVAC Product Manager, said the Spiracoustic Plus portfolio was expanded to make installation easier and faster for smaller diameter ducts, and, more importantly, to give customers and contractors a needed market solution.

“Our one-inch, very small diameter (VSD) Spiracoustic Plus duct liner is listed to fit in duct sizes all the way down to 8 inches in diameter. However, we know that installing VSD Spiracoustic Plus in ducts with an 8-inch O.D. can be challenging. That’s why we decided to engineer VVSD Spiracoustic Plus – to give installers access to a range of insulations specifically designed to fit the full range of duct sizes. VVSD is manufactured with smaller, evenly spaced kerfs, for a smoother installation into 6-inch and 8-inch diameter ducts,” Hall said.

Like the other sizes in the Spiracoustic Plus duct liner portfolio, VVSD is bonded with a thermosetting resin and is specifically engineered to provide excellent acoustical and thermal performance in spiral ducts. The airstream surface and transverse edges are protected with JM’s factory-applied, black Permacote® acrylic coating for added protection for the airstream surface.

VVSD offers a more ideal solution for the smallest duct sizes and is now available to customers in the United States and Canada. For more information on Spiracoustic Plus Duct liner, 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 46 manufacturing facilities in North America, Europe and China. Additional information can be found at