Unique Dual Density Technology

Producing resilient and robust slabs for external applications

ROCKWOOL has pioneered innovative Dual Density technology through a specialist manufacturing process. Comprised of a high-density outer layer and a lower-density sub-layer, Dual Density products provide compressive resistance, excellent sound absorbency and many other benefits for different applications. Dual Density stone wool products in the United Kingdom are supplied exclusively by ROCKWOOL and its distribution network. 

This specially developed technology is instrumental in the performance and success of RAINSCREEN DUO SLAB® for façade systems, Thermal ROCKFLOOR for ground floors and the HARDROCK Multi-Fix DD range for flat roofs.

RAINSCREEN DUO SLAB

ROCKWOOL RAINSCREEN DUO SLAB® is a non-combustible thermal insulation for ventilated rainscreen and overcladding applications. The Dual Density slab has a resilient surface for accepting mushroom-head fixings, whilst the underside absorbs any imperfections or unevenness in the substrate. The robust outer surface and inner face are also an effective protection against adverse weather conditions. 

The fibres of adjacent slabs knit together when tightly butt jointed, eliminating any gaps through which heat can be lost. Requiring minimal fixings, RAINSCREEN DUO SLAB® saves valuable time and money on installation. 

Alongside the excellent sound absorption properties offered by ROCKWOOL stone wool, the change in density between the two layers provides an additional benefit in that it causes soundwaves to be reflected at the interface, further enhancing the acoustic performance.

RAINSCREEN DUO SLAB® is the first and only stone wool product to receive BBA approval for use in ventilated rainscreen systems following rigorous testing regimes. ROCKWOOL Dual Density technology played a significant part in the recognition of the product.

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Crowne Plaza Hotel - Heathrow Airport Terminal 4 - RAINSCREEN DUO SLAB

HARDROCK Multi-Fix (DD)

Compatible with a range of flat roof systems, ROCKWOOL HARDROCK Multi-Fix DD provides exceptional acoustic and fire resistance properties. The Dual Density  composition gives a high-density top surface which exhibits excellent compressive resistance, engineered to last for the lifetime of the building. 

Despite its robust nature, the board is easy to cut, shape and install. As only one fixing is typically required per board for mechanically fixed roof systems, HARDROCK Multi-Fix DD reduces installation time and costs. 

ROCKWOOL Dual Density technology in the HARDROCK Multi-Fix DD roofing system means the boards provide both mass and absorption for superior acoustic performance, which can eliminate the requirement for additional mass layers allowing performance criteria to be met through the insulation alone. 

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Queen Elizabeth Stadium

Thermal ROCKFLOOR®

The unique dual density structure of Thermal ROCKFLOOR® means the slabs can absorb sub-floor imperfections on one side, and provide a high level of compressive strength on the other. The slabs are also easy to handle and fit.

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Home, floor, carpet, living room, couch