Knauf Rocksilk RS60 25mm Building Slab

The 25mm Rocksilk RS60 from Knauf is a standard-density (60kg/m3) mineral wool insulation slab engineered for superior thermal and acoustic performance. This non-combustible material achieves Euroclass A1 classification, the highest rating for fire safety, making it ideal for new builds and refurbishment work alike.

Sized at 1200mm x 600mm, each insulation slab delivers outstanding thermal efficiency with a certified λ value of 0.035W/mK. The unfaced design offers flexibility across multiple applications, from internal partitions to timber and metal stud work, and between rafters and floor joists.

These slabs are naturally odourless, non-hygroscopic, and completely rot-proof. Free from CFCs and HCFCs, they resist fungal growth, mould, and bacterial colonisation, ensuring long-term durability and safety.

The material excels in sound absorption, delivering significant acoustic performance alongside thermal benefits. Installation is straightforward—simply cut and shape using a large-bladed knife or saw.

Product specification

• Brand: Knauf®
• Model: 25mm Rocksilk RS60
• Thickness: 25mm
• Length: 1200mm
• Width: 600mm
• Dimensions: 1,200mm x 600mm x 25mm
• Board Coverage: 0.72m2
• Pack Coverage: 12.96m2
• Pack Quantity: 18
• R-Value: 0.70m2K/W
• Thermal Conductivity: 0.035W/mK
• Density: 60kg/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

Rocksilk Building Slabs provide versatile solutions across numerous building scenarios. Use them between rafters in pitched roof systems, within intermediate floors and separating floors, or as infill in internal stud partitions and light steel frames. These slabs are also popular in OEM (Original Equipment Manufacturer) applications for producing thermal, acoustic, and fire-rated products. With non-combustible properties and available densities ranging from 45kg/m3 to 140kg/m3, they suit a wide spectrum of building requirements.

Benefits

• Single slab solution for diverse building applications
• Factory-applied foil or tissue facing options available for extended project flexibility
• Rock mineral wool construction delivers superior sound absorption compared to conventional alternatives
• Melting point exceeding 1000°C provides extended fire resistance performance versus standard insulants

Info

Browse our complete Knauf Insulation range and refine by thickness or coverage using the left-hand filters. Need advice on product suitability for your project or a bulk discount quote? Contact us on +4402038839057, email sales@insulationbee, or use Live Chat for the best UK Knauf Loft Insulation prices.