Rock Mineral Wool - Knauf Insulation Rocksilk® Soffit Linerboard Standard

Knauf Insulation Rocksilk® Soffit Linerboard Standard


Structural soffit floor


Rock Mineral Wool


Rocksilk® Soffit Linerboard Standard is a rock mineral wool slab, designed to insulate non-exposed structural soffits in applications such as underground car parks.

It is non-combustible with the best possible Euroclass A1 reaction to fire classification, and is manufactured using our unique bio-based binder, ECOSE® Technology.


  • Available both unfaced and with a black tissue facing, for use in non-exposed soffit applications.
  • Provides a solution to upgrade thermal performance of existing floors without reducing floor height.
  • Can be installed without the need to access areas above the floor.
  • Manufactured from mineral wool which provides the best levels of sound absorption and reduction compared to other mainstream insulants to reduce the sound transfer between storeys.
  • Available with optional fixings which match the colour of Rocksilk® Soffit Linerboard Standard and Extra.

For historical versions of product documentation, or documents relating to any discontinued products, please contact us with your requirements at [email protected].  



Thickness (mm) Length (mm) Width (mm) Thermal Conductivity (W/mK) R-value (m²K/W) Euroclass Reaction to Fire Classification Quantity per pack
50 1200 600 0.034 1.45 A1 6
75 1200 600 0.034 2.20 A1 4
130 1200 600 0.034 3.80 A1 40
160 1200 600 0.034 4.70 A1 32
185 1200 600 0.034 5.40 A1 28
220 1200 600 0.034 6.45 A1 20

Certification & Memberships

Eurofins Gold Eurofins Gold
Euroclass A1 Reaction to Fire Classification Euroclass A1 Reaction to Fire Classification
CE Marking CE Marking
Green Guide Rating A Green Guide Rating A
EN 15804 EN 15804
Made in Britain Made in Britain


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