Rock Mineral Wool - Rocksilk Krimpact Flat Roof Slab


Flat roof


Rock Mineral Wool


Rocksilk Krimpact Flat Roof Slabs are  high performance, non-combustible Rock Mineral Wool slabs with high compressive strength, suitable for use on all types of roof deck, and can be overlaid either with a single ply membrane which is mechanically fixed, or with a waterproof membrane consisting of either a fully bonded built-up bitumen roofing system, or mastic asphalt.

Slabs contain a special additive to ensure their water repellency.


  • Excellent thermal performance.
  • Non-combustible A1 Euroclass Reaction to Fire classification
  • Absorbant nature of the product reduces the drumming effect of rainwater
  • Manufactured using specialist Knauf Insulation Krimpact Technology for high levels of compressive strength and durability
  • The nature of Rock Mineral Wool allows slabs to knit together at joints
  • Dimensionally stable 
  • Compatible with a wide range of single ply membranes



Thickness (mm)Thermal Conductivity (W/mK)R-Value (M²K/W)Euroclass Reaction to Fire ClassificationLength (mm)Width (mm)Area Per Pallet (m²)Slabs Per Pallet


BBA Certificate 08_4526 Rocksilk Krimpact Flat Roof Slab
Eurofins Gold
A1 Euroclass Fire Rating
CE Marking
Bureau Veritas
Green Guide Rating B-C

Declaration of Performance

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Additional Product Information


We care for the people who make our products, the people who use them and the world we all depend on.

 Whilst we are dedicated to supplying sustainable high performance insulation solutions for enhanced energy efficiency in buildings, we also continually strive for improvements in our manufacturing and supply chain operations so to improve quality and minimise our impact on the environment. All Knauf Insulation production locations have state-of-the-art manufacturing equipment and meet the highest quality standards as well as they are supported by an ongoing research and development program. All of our products including Rocksilk Krimpact Flat Roof Slab are sustainably manufactured.

At Knauf Insulation, we have 7 key sustainability considerations:

  • to conserve natural resources
  • to reduce the evironmental effects of our own processes
  • Treating people fairly, along the supply chain
  • Delivering our products efficiently
  • Building a comfortable and healthy indoor environment
  • Performance reporting
  • Recognition