Knauf External Wall Insulation (EWI) Slab

Last Updated: September 18, 2015 08:04

Rocksilk EWI Slab and EWI Slab Plus are high strength, rock mineral wool slabs with a water repellent additive specifically designed for use in external wall insulation systems.

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Product Details

Rocksilk EWI Slab and EWI Slab Plus are specifically for use with external wall insulation systems. The slabs can be either adhered and mechanically fixed or just mechanically fixed to the substrate then overlaid with a mesh and render system to the designers / system suppliers specification. The slabs offer a solid and robust supporting substrate for the render and no fire stops are required.

Rocksilk EWI Slab and EWI Slab Plus are manufactured in accordance with BS EN 13162:2008, EN 16001:2009 Energy Management Systems, OHSAS 18001:2007 Occupational Health and Safety Management Systems, ISO 14001:2004 Environmental Management Systems, and ISO 9001:2008 Quality Management Systems, as certified by Bureau Veritas. Rocksilk EWI Slab and EWI Slab Plus are classified as Euroclass A1 BS EN ISO 13501-1.

Krimpact™ Technology realigns the mineral wool strands during manufacture to increase compressive strength without dramatically reducing thermal performance – making Rocksilk Krimpact EWI Slab an ideal product for use behind a render finish. Furthermore, Krimpact Technology achieves a consistent density slab. This ensures better long-term compressive strength, high impact resistance, better thermal performance and a thinner, lighter product compared to other high-strength insulation options.

Please note - only ThermoShell EWI Approved Installers can purchase these EWI products. Visit the training page to see details of the Knauf EWI Training Course.

Specification & Product Codes



Mineral Wool

Environmental statement:
Zero ODP, Zero GWP, Euroclass A1, BS EN ISO 13501-1
ISO 14001:
Quality certification:
OHSAS 18001:2007, EN 16001:2009, BS EN 13162:2008, Euroclass A1 to BS EN ISO 13501-1



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