Knauf Rocksilk RS140 100mm Building Slab

The 100mm Rocksilk RS140 Knauf Rock Mineral Wool Insulation Slab delivers outstanding thermal and acoustic performance with a standard density of 140kg/m3. This non-combustible material achieves Euroclass A1 classification, the highest rating available for fire safety in building applications.

Sized at 1200mm x 600mm, this insulation slab suits both new builds and refurbishment work. The product is odour-free, non-hygroscopic, and naturally rot-proof, containing no CFCs or HCFCs whilst resisting fungal, mould, and bacterial growth.

With a certified thermal conductivity of 0.034W/mK, the 100mm RS140 unfaced slab provides reliable thermal efficiency. At 140kg/m3 density, it works well for internal partitions, timber and metal stud work, and positioning between timber rafters and floor joists.

The material excels at absorbing sound, delivering substantial sound reduction benefits. Installation is straightforward—simply cut and shape using a large-bladed knife or saw for a practical fit.

Product specification

• Brand: Knauf®
• Model: 100mm Rocksilk RS140
• Thickness: 100mm
• Length: 1200mm
• Width: 600mm
• Dimensions: 1,200mm x 600mm x 100mm
• Board Coverage: 0.72m2
• Pack Coverage: 1.44m2
• Pack Quantity: 2
• R-Value: 2.90m2K/W
• Thermal Conductivity: 0.034W/mK
• Density: 140kg/m3
• Colour: Brown
• Material: Rock mineral wool
• Fire Classification: Euroclass A1
• Vapour Resistivity: 5.00MNs/g.m.
• Fire Reaction: Non-combustible
• Building Regulations: Class '0'
• Finish: Unfaced
• Shipping method: Articulated Vehicle ǀ Courier
• Applications: Floor ǀ Wall ǀ Roof ǀ Partitions
• Foil faced: No
• ECOSE Technology: Yes
• ETA Notification: Yes
• Features: Thermal and Acoustic Insulation Performance
• Manufacturer: Knauf Rocksilk®

Made to order Facings

For a factory applied foil or tissue facing please request a quotation using the website form or by calling our agents. We do offer single side or double side foil/tissue facings.

Applications

100mm Rocksilk Building Slabs work across numerous settings, from pitched roof spaces between rafters to intermediate floors and separating floors. They're equally suited to internal stud partitions and light steel frame infill. OEM (Original Equipment Manufacturer) applications benefit from these slabs when fabricating thermal, acoustic, and fire-rated products. Rocksilk® Building Slabs are non-combustible and available across a density range from 45kg/m3 to 140kg/m3, making them adaptable for diverse project requirements.

Benefits

• One slab type handles multiple applications across your project.
• Factory-applied foil or tissue facing options are available, expanding the range of suitable uses.
• Rock mineral wool construction delivers superior sound absorption and noise reduction versus standard insulation alternatives.
• With a melting point above 1000°C, rock mineral wool provides extended fire resistance compared to many competing products.

Info

Explore our full Knauf Insulation range and refine by thickness or coverage using the filters on the left. Need advice on product suitability for your project or a bulk discount quote? Get in touch by phone on +4402038839057, email sales@insulationbee, or use Live Chat for the best UK Knauf Loft Insulation prices.