Product description

With the exception of schools, very few buildings are governed by external noise control standards, yet where flat roofs are concerned, multiple sound sources, especially rain fall… can cause disruption in the interior environment. This is where HARDROCK® Multi-fix (DD) comes in. Compatible with a range of roofing systems, this ROCKWOOL solution provides exceptional acoustic and fire resistance properties.


ROCKWOOL HARDROCK® Multi-Fix (DD) boards are manufactured from renewable volcanic stone which produces a non-combustible roofing insulation board. The solution is compatible with a range of flat roof systems such as; single-ply, EPDM membrane systems, green roofs, bitumen and liquid membranes.


HARDROCK® Multi-Fix (DD) boasts an extremely high acoustic performance, especially in conjunction with ROCKWOOL Acoustic Infill and ROCKWOOL Acoustic Membrane for robust fire resistant and acoustic properties in flat roof insulation.


Tested to the highest European fire classification, HARDROCK® Multi-Fix (DD) meets the highest LPCB standards. It has also achieved European Reaction to Fire Classification of A1 noncomputability. In the specification of fire resistant insulation, it is crucial to consider characteristics such as combustibility and toxicity. HARDROCK® Multi-Fix (DD) provides an acoustically sound, non-combustible and non-toxic solution to flat roof insulation.



Euroclass A1 non-combustible, LPCB & FM approved.


  • Achieves Euroclass A1 non-combustibility, a robust solution for consideration of fire performance.
    LPCB (LPS 1181: Part 1 Ext A) and FM approved to meet the highest European fire classifications.
  • Excellent acoustic reduction, absorption and impact performance – whether from people, machinery or rain on the roof.
  • HARDROCK® Multi-Fix (DD) is dimensionally stable and will provide long term consistent thermal performance over its lifetime.
  • A sustainable solution, made from natural materials, HARDROCK® Multi-Fix (DD) can be recycled and reprocessed, reducing landfill costs with zero ODP and GWP.
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